What can we expect from Season 3?

All in all you can say: more champions, more items, more reworks, new masteries, new runes, a new jungle and increased presence in esports.

Champions:

Pre-Season 3 starts with the release of Nami, a brand new support. And it goes on with another female champion. Morello mentioned a "badass female champion" - who will be released at the end of 2012. In summer, Morello also talked about new champions and promised some new monsters, just as wished by the community. There are several reworks in progress, e.g. the already mentioned Karma rework and a Heimerdinger rework. Trundle will get a sligthly rework aswell.

Items:

Morello pusblished a few days ago the current item changes. They are now available on PBE servers and may be changed till the rest of us will receive the patch:

General:
Basic Stat Valuations have Changed - This means that the amount of statistics you get per point of gold has shifted.
Attack Damage is generally cheaper from 5 to 10% across all items.
Attack Speed is generally around 10 to 20% more expensive than before.
Armor and Magic Resistance is generally around 10 to 20% more expensive than before
Many items have had their statistics slightly adjusted around this fact.
In general, high-end item premiums have been reduced across the board. This means that items are generally more expensive or provide less statistics the higher tier they are.

Offensive Auras
Range increased to 700 from 600 - Abyssal Scepter, Frozen Heart.

Defensive Auras
Ranges are now consistent at 1100 - Aegis of the Legion, etc.
Penetration
Flat Penetration items have had their values reduced.
Percent Penetration items have had their values reduced.
Slowing Effects
Global Slow particle now appears faster
Slow effects on Phage / Trinity Force now have reduced effect when used by ranged characters.
Slow durations on Phage / Trinity Force / Frozen Mallet reduced slightly.

General (Boots)
Movement Speed
Boots give 25 less movement speed across the board.
All champions have had their base movement speed increased by 25.
Tier 2 boots can be enchanted, upgrading them to a Tier 3 boot for some gold.
Homeguard: Provides powerful regeneration and movement speed at fountain.
Furor: Increased movement speed in combat.
Captain: Increases movement speed of allies moving toward you.
Distortion: Decreases cooldown of Ghost, Teleport and Flash.
Alacrity: Grants a small additional base movement speed bonus.

Removed
The following items are no longer available and items that built out of them have had their recipes changed:
Meki Pendant, Regrowth Pendant, Force of Nature, Ionic Spark, Moonflair Spellblade, Cloak and Dagger, Elixir of Agility, Leviathan.
The following items are no longer available on Summoner's Rift and items that built out of them have had their recipes changed:
Heart of Gold

Reworked
Doran's Items
Doran's items have slightly less statistics but each has gained an additional passive
Doran's Blade
Has 0% Life Steal
Passive: Recovers a small amount of life on hit
Doran's Ring
Lost a little bit of regeneration.
Passive: Gain a small amount of mana on kill.
Doran's Shield
Lost some health regeneration and armor.
Unique Passive: Blocks a small amount of damage from champion basic attacks.
Giant's Belt
Slightly cheaper but grants less health.
Rageblade
Reworked to have a powerful attack speed, spell vamp and life steal boost when you are low on life.
Aegis of the Legion
Lost attack damage, gained health regeneration
Builds out of Emblem of Valor instead of Ruby Crystal.
Lich Bane
No longer grants magic resistance.
Now deals magic damage equal to a base damage plus a percentage of your AP ratio.
Vamp Scepter
Now builds out of a long sword and grants attack damage.
All items that build out of Vamp Scepter now grants attack damage.
Zeke's Herald
No longer grants attack speed or builds out of a dagger.
Avarice Blade
Gives less critical strike
Grants an additional 2 gold per kill.
Hextech Gunblade
Active has had its base damage reduced and now has an AP ratio.
Single target attacks and spells versus champions reduce the cooldown of the active by 3 seconds.
Phantom Dancer
Grants less move speed and less attack speed.
Grants 'Ignore Unit Collision' passively.
Shurelya's Reverie
Grants far less regeneration statistics total.
Eleisa's Miracle
Does not grant Tenacity
Lowers Heal, Clairvoyance and Revive cooldowns by 20%
Gaining 3 levels with the item gives you the stats and passive permanently and the item disappears from your inventory.
Black Cleaver - Remade
Builds out of Brutalizer + other items
Dealing Physical damage reduces a % of the target's armor.
Youmu's Ghostblade
Active simplified - 6 for melee, 4 for ranged.
Active cooldown reduced to 45 from 60.
Warmog's Armor
Stacking passive removed.
Now regenerates 1.5% of your maximum health every 5 seconds.
Deathfire's Grasp - Remade
Now builds out of Needlessly Large Rod and an Amplifying Tome.
Grants large amounts of AP and CDR%.
Unique Active: Deals 15% of the target's maximum health and amplifies magic damage done to the target by 20% for 4 seconds.
Warden's Mail
Recipe: Cloth Armor + Cloth Armor
Passive no longer random - but the effects are reduced.
No longer grants regeneration.
Warden's mail only reduces attack speed.
Builds into Frozen Heart.
Randuin's Omen
Passive no longer random - but the effects are reduced.
Randuin's Omen will reduce attack speed and movement speed.
Base duration on active increased to 2 seconds from 1.
Tears of the Goddess
Slightly cheaper
Now triggers when you spend mana as well as spellcasts.
Archangel's Staff
Upgrades into Seraph's Embrace when the Tears of the Goddess passive is fully charge.
Seraph's Embrace
Activate to shield yourself for 25% of your current mana for 2.5 seconds.
Manamune
Upgrades into Muramana when the Tears of the Goddess passive is fully charged.
Muramana
Toggle to deal a % of your current mana in magic damage on basic attacks and spells.
Tiamat
Melee only
Now a Unique Passive with a larger splash radius and damage falloff near the edge.
Now has an active: Activate to cleave in a large area around your target.

Consumables
Oracle Elixir
Duration capped at 5 minutes.
Elixir of Strength
Duration reduced to 3 minutes
Slightly stronger effect at early levels.
Elixir of Brilliance
Duration reduced to 3 minutes.
Slightly stronger effect at early levels.

New Items
Kage's Last Breath
Supportive Peel/Initiation Item
Recipe: Kage's Lucky Pick, Mana Manipulator
Keeps G/10 Passive.
Active: Target ally gets a 30% slow aura for 3 seconds - 60 second cooldown.
Liandry's Lament
Controlled Burn Mage Item
Recipe*:* Haunting Guise, Amplifying Tome
Passive: Dealing spell damage burns enemies for a % of their current life over 3 seconds. This effect deals double damage if the target's movement is impaired.
Statikk Shiv
High Speed / Burst Damage Item
Recipe*:* Zeal, Avarice Blade
Passive: Moving or Attacking builds static charges. At 100 charges, your next attack unleashes all charges to deal 100 magic to up to 4 targets. This effect benefits from critical strikes.
Frozen Fist
Resistance oriented version of Sheen
Recipe: Sheen + Glacial Shroud
Passive: After using an ability, your next attack deals physical damage equal to 125% of your base attack damage to surrounding enemies. This leaves an icy field that slows enemy movement speed by X% for Y seconds.
Bloody Hydra
High End Attack Damage / Area of Effect Item
Recipe: Tiamat + Vamp Scepter
Passive: Tiamat's active and passive now benefits from a percentage of your life steal.
Mercurial Scimitar
High End Magic Resistance / Attack Damage Item
Recipe: Quicksilver Sash + B.F. Sword
Active: Cleanses all debuffs from your character. If your character is melee, he gains 100% movement speed for 1 second.
Ohmwrecker
High End Siege Item
Recipe:Catalyst + Chain Vest
Active: Disables nearby enemy towers for 2.5 seconds, preventing them from attacking.
Wraith Collar
Supportive Scouting Item
Recipe: Kage's Pick + Null Magic Mantle
Active: Summons 2 wraiths for 6 seconds that seek the nearest enemy champions. If they reach an enemy champion, they slow him and reveal him for 2.5 seconds.
Hurricane
Ranged-Only Area of Effect Item
Recipe: Dagger + Recurve Bow + Dagger
Passive: Your shots fire two secondary ghostly bolts that deal X + 50% of your attack damage to nearby targets. These cannot critically strike but apply on-hit effects.
Zephyr
High End Speed Item
Recipe*:* Stinger + Long Sword
Grants Attack Speed, Cooldown Reduction, Movement Speed, Attack Speed and Tenacity.
Banner of Command
Siege Mage Item
Recipe: Blasting Wand + Emblem of Valor
Unique Aura: Grants health regeneration to nearby allies
Unique Aura: Grants % damage to nearby minions.
Active: Promotes a nearby siege minion to a super minion. You get all the gold from this minion's kills - 120 second cooldown.
Sword of the Divine
Rapid Burst Attack Damage Item
Recipe: Recurve Bow + Dagger
Active: You gain 100% attack speed and 100% critical strike for 4 seconds or 3 critical strikes - 25 second cooldown. This item gives no attack speed while on cooldown.
Passive: Kills and assists halve this item's cooldown.
Mikael's Crucible
High Tier Supportive Item
Recipe: Chalice + Sapphire Crystal
Passive: Increases mana regeneration based on missing mana.
Active: Removes stuns, roots, silences, slows, fears and taunts from an ally and then heals them for X + Y% of their missing health - 3 minute cooldown.
Consumables
Sight Stone
Supportive Ward Item
+X Health
Passive: Starts with 4 charges, charges refill when you go back to fountain.
Active: Consumes a charge to place a sight ward that lasts 3 minutes. You may have a maximum of 2 wards from the item at once
Ruby Sight Stone
Supportive Ward Item
Recipe*: Sight Stone* + Ruby Crystal
Passive: Starts with 5 charges, charges refill when you go back to fountain.
Active: Consumes a charge to place a sight ward that lasts 3 minutes. You may have a maximum of 3 wards from the item at once
Leaden Crystal Flask
Supportive Regeneration Item
Passive: Starts with 3 charges, charges refill when you go back to fountain.
Active: Consume a charge to regenerate 100 health and 40 mana over 10 seconds.


Summoner Spells:

In the beginning of Season 2, Flash and Clairvoyance got nerfed because of its big impact. While Flash was still viable and its nerf was needy, Claivoynace became a unusefull summoner spell and supports are using Exhaust instead. The changes for Season 3 are now:

Newly available
Barrier is now available on all maps to give players a selfish defensive option
Values rebalanced accordingly
Cooldown increased
Duration and damage absorbed reduced
Modified
Exhaust's values have been modified to reduce its impact on melee champs and increase its visibility
Physical damage reduction reduced, but now also reduces attack speed
Clairvoyance has been modified to focus more on hitting clairvoyance on players rather than zoning them out of an area
Improved clairvoyance now reveals champions hit by clairvoyance for the duration even if they walk out of the circle
Radius, duration, and cooldown modified as well
Clarity has been modified to restore mana based on mana pool rather than a flat value
Heal has been tuned to be a team supporting defensive option
Allies are now healed for the same amount as the caster
Health values and cooldown have been retuned accordingly
Flash, Ignite, and Revive have also had minor changes
Removed
Surge and Promote have been removed

Masteries:

New Masteries, new skilling combinations

Offensive Tree:
Summoner's Wrath: Exhaust lowers targets MR/Armor by 10, Ignite gives +5 AD / AP when on CD, Ghost speed increased to 35%, Allied Garrisoned turrets deal 50% splash damage.
Fury: + 1/2/3/4% attack speed
Sorcery: + 1/2/3/4% CDR
Butcher: + 2/4 damage to minions.
Deadliness: + 3/6/9/12 AD at level 18 ( .17 AD per rank per level )
Blast: + 4.5/9/13.5/18 AP at level 18 ( .25 AP per rank per level )
Destruction: Increase damage to turrets by 2.5/5%
Havoc: Increase damage by 0.67/1.33/2%
Weapon Expertise: 8% Armor Pen
Arcane Knowledge: 8% Magic Pen
Lethality: + 2.5/5% Critical Strike Damage (5%/10% for melee champs)
Brute Force: + 1.5/3 AD
Mental Force: + 1.5/3/4.5/6 AP
Spellsword: deals 5% of your AP as magic damage in each autoattack
Frenzy: Grants 10% attack speed for 2 seconds after landing a crit hit.
Sunder: +2/4/6 Armor Pen
Archmage: +1.25/2.5/3.75/5% bonus AP
Executioner: Increase damage by 5% to targets below 50% health
Defensive Tree
Summoner's Resolve: Increases the duration of Cleanses disable reduction by 1 sec,  Heal grants +5 champion HP per level, +10 gold on smite use, increases Barrier amount by 20
Perseverance: up to 2/4/6 health regen per 5 based on missing health
Durability: + 27/54/81/108 health at level 18 ( 1.5 hp per rank per level )
Tough Skin: reduce damage taken from monsters by 1/2
Hardiness: + 2/4/6 armor
Resistance: + 2/4/6 MR
Bladed Armor: Deals 6 damage to any enemy monster that attacks you
Unyielding: Reduce damage taken by champions by 1/2
Relentless: Reduce effectiveness of slows by 7.5/15%
Veteran's Scars: +30 health
Safeguard: Reduce damage taken from turrets by 5%
Block: Reduce damage taken from champion basic attacks by 3
Tenacious: Reduces the duration of crowd control effects by 5/10/15%
Juggernaut: Increase your max health by 1.5/2.75/4%
Defender: + 1 armor and MR per nearby enemy champion
Legendary Armor: + 1.25/2.5/3.75/5% armor and MR
Good Hands: Reduce time spent dead by 10%
Reinforced Armor: Reduce damage taken from critical strikes by 5/10%
Honor Guard: Reduce damage taken from all sources by 3%
Utility Tree
Summoner's Insight: Grants bonus health on Revive for 2 min, reduces teleport cast time by .5 sec, reduces cooldown of flash by 15 seconds, increases Clarity's mana restore by 25%, Grants additional vision of enemy units revealed.
Wanderer: + 0.66/1.33/2% MS when out of combat
Meditation: +1/2/3 mana per 5
Improved Recall: Reduces cast time of recall by 1 sec and improved Recall by .5
Scout: Wards gain 25% increased vision for the first 3 seconds
Mastermind: Reduces the cooldown of Summoner Spells by 4/7/10%
Expanded Mind: + 72/126/180 mana at level 18 ( +4 per rank per level )
Artifacer: Cooldown of activated items are reduced by 7.5/15%
Greed: +0.5/1/1.5/2 GP10
Runic Affinity: +20% buff duration
Strength of Spirit: + up to 1/2/3 HP per 5 for each 400 points of mana you posses
Biscuiteer: Start the game with a regenerative biscuit that restores 80 health and 50 mana over 10 seconds
Wealth: Increase starting gold by 25/50
Awareness: increase experience earned by 1.25/2.5/3.75/5%
Vampirism: +1/2/3% lifesteal and spellvamp
Explorer: On Summoner's Rift, grants a ward at the start of the game that can be placed to reveal the surrounding area for 60 seconds. On all other maps, +25 starting gold
Pickpocket: +3 gold ( ranged)/+5 gold melee for each basic attack against an enemy champion has a 5 second cooldown
Intelligence: +2/4/6% CDR
Nimble: +3% MS


Runes:

Several runes became a rework because of the Armor Penetration changes


Jungle:

The jungle changes will propably have the most impact into current meta. After easying jungle in season 2, counterjungling and ganks were increased and the jungler could
win a lane with a single good gank. To entices jungler to stay in the jungler and make ganks less successful, there will be major jungle changes:

General
Leashing has been changed
Jungle monsters now attack the closest hostile target rather than chasing their original target until reaching their range limit
Whenever jungle monsters switch targets it counts as a “leash” - the maximum amount of leashes after which jungle monsters will reset has been increased
Jungle monsters now deal bonus damage to summoned minions
Initial difficulty of all jungle camps has been increased
Overall camp Health has been increased
Camp difficulty and rewards have been re-distributed more into the large monster in each camp
The largest monsters at each camp are generally more resilient but also hold most of the rewards
Scaling difficulty and rewards of the primary jungle camps has been significantly increased
Health and Attack Damage growth per minute significantly increased
Gold and Experience growth per minute significantly increased
Overall rewards have been re-distributed between the 3 primary jungle camps (Wolves, Wraiths, Golems) to better match their difficulty and convenience
Wraiths are the fastest-respawning, most convenient camp and have the lowest rewards
Golems and Wolves are more difficult and are worth more
New jungle items have been added to the store and old jungle items have been adjusted
Hunter’s Machete - new jungle starting item that builds into Madred’s Razors and Spirit Stone
Spirit Stone - jungle item geared towards casters and tanks that has 3 upgrade paths
Madred’s Razors and Wriggle’s Lantern have been modified to build out of Hunter’s Machete
The “Banking” system that caused jungle monsters that have stayed alive for a long duration to have slightly increased rewards has been removed
Wolves
Critical Strike damage bonus reduced to better normalize damage output
Movement Speed slightly reduced
Wraiths
Reduced their vulnerability from enemies that engage them from outside of the camp
Camp has been repositioned
Big Wraith’s Attack Range has been reduced
Golems
Movement Speed and Attack Range increased to reduce vulnerability from kiting
Magic Resist reduced to negative values


League of Legends in esports:

Currently, Riot creates an own international pro league. The matches will be weekly streamed in "television-broadcast quality" for free. Weekly matches will cukinate in regional playoffs and evenutally end in a World Championship.

When will Season 3 start?

We are currently in Week 2 of Pre-Season 3, the start of Season 3 is currently set to end of 2012/ beginning 2013
 

That was the last part of the full recap of Season 2 and a little preview for Season 3. See you on the field of Justice!

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