In any MMOG, even in expansions, there's a seemingly endless amount of content to discuss. If you didn't read IGN's preview or interview with lead producer J. Allen Brack, here's a chat with lead designer Jeffrey Kaplan.
He gives IGN details on how the new Death Knight class will work, how quests are generally being restructured, and about the changes to the game's raiding structure. Please note that if you're not a World of Warcraft player, little of this interview will likely make sense.