News straight from the WWI.
These are confirmed public release notes from WOTLK

Druid
  • Entangling roots will be useable indoor.
  • Nourish will be a new healing spell, healing for more hit points for each HoT effect on the target.

Hunter
  • All kind of pets will have their own talent tree. A tanking talent tree, a DPS talent tree, and an utility talent tree. Each kind of pet family will have its own talent tree and its own unique ability.
  • The shot clipping will be removed from Steady Shot, you'll be able to use it without "interrupting" your autoshot. Hunters will be able to just smash their button.
  • There are going to be new pets in WotLK.
  • The skill points for each pets are being changed to the new "Pet talents" and will disappear.

Priest
  • Divine Hymn will be a deep-holy talent protecting your party from attackers, any attacks done to you or your party will cause the attacker to be afflicted by sleep.
  • The 51 point talent for Shadow Priests is Dispersion : You disperse into pure shadow energy, reducing all damage taken by -90%. You are unable to attack or cast spells, but you regenerate 6% health and mana every 1 sec for 6 seconds.
  • Guardian Spirit - Calls upon a guardian spirit to heal and watch over the friendly target. The spirit heals the target for 642 every 2 sec, and also prevents the target from dying by sacrificing itself. Lasts 10 seconds.

Mage
  • Mages are getting a Frostfire bolt dealing Frost-Fire damage to make elementalists more viable.

Shaman
  • Totems are being "condensed" into a smaller amount of totems, for exemple Strength of Earth and Grace of Air totems will be merged into the same totem
  • A new weapon enchantment will be available "Earthliving Weapon". It will increase the healing power of the Shaman.
  • Flametongue will give spell damage bonus to the Shaman.
  • Totems are being moved to physical school, you can't counterspell anymore.
  • Totems will also affect raid members, not just the local party.
  • Shamans are getting "Hex", a polymorph-like spell on a medium cooldown allowing them to turn an enemy into a frog. The enemy cannot cast or attack but is still in control of his character.
  • Windfury won't be a weapon enchant anymore and will be changed to a buff. You will be able to use it in bear form or with poison.

Rogue
  • Rogues will get a talent called "Fan of Knives", an AoE ability allowing them to attack all enemies within a short range. It will be some kind of "emergency" ability and you won't be able to spam it.
  • Sap will now work on more targets, humanoids, beasts, dragonkins, demons. "Anything with a skull and a brain inside of it".

Paladin
  • Retribution paladins itemization will be moved to the same item as Warriors/Death Knights
  • A new reactive healing spell will be added - Hand of Purity.

Warlock
  • Demonic Circle will allow warlocks to scribe a circle in the ground to teleport to it later with another spell.
  • The 51-Point demonogy talent is a Demon-Form, this will allow you cast AOE Shadowbolts

Warrior
  • Titan's Grip will allow warriors to wear 2 hand weapons with a single hand.
  • Protection Warriors are getting a spell called "Shockwave" allowing them to damage and stun all the monsters in front of them.
I know we've seen most of them before, but there doing a couple of sweet things to the shaman.

They've also released information about diablo 3, there are some really tidy screenshots available up on the just added D3 website.
http://eu.blizzard.com/diablo3/ for the lazy people