Check out this tour of the zones of World of Warcraft: The Catacylsm, for a look at Gilneas, The Lost Isles, and how Deathwing's reappearance will forever change the face of Azeroth.

New lands are all well and good, but seeing places where I've spent countless hours over the past five years completely changed is simply spectacular. Changing the existing world so drastically is an amazingly elegant way of adding new content without slapping another undiscovered landmass or alternate dimension to the game.