Two new races are available! The Worgens for the Alliance, and the Goblins for the Horde!
7 New dungeons have been added to the game: Blackrock Caverns, Grim Batol, Halls of Origination, The Stonecore, Throne of the Tides, Vortex Pinnacle, Lost City of the Tol'vir. Also, two old dungeons have been fully revamped and are now available in a new lvl 85 heroic version: The Deadmines and Shadowfang Keep.
5 new high level zones have been added to the game: Twilight Highlands, Uldum, Deepholm, Mount Hyjal, Vashj'ir. The Goblins and Worgens starting areas also have their own zones: Gilneas, Kezan, Lost Isles
Guild Leveling and Rewards
The new Guild Rewards and Guild Leveling / Perks are also added to the game with the expansion!
Tons of super-awesome items are being added to the game, see the most significant additions below!
All professions have been updated with new items and bonuses. Archaeology is now available!
Player vs. Player
3 new PvP zones are added to the game: Tol Barad (Outdoor PvP, Wintergrasp-like), Twin Peaks (Battleground), Battle for Gilneas (Battleground)