I've been monitoring Requiem's (my old raiding guild) message boards to get some firsthand accounting on how the new expansion is going. Based on the few postings I've read, it would seem not well. Guildees are reporting queues that exceed one thousand! Another guildee reported that his WotLK DVD didn't even work. After multiple install attempts, he had to download the game from another source.
I haven't read any feedback regarding actual gameplay yet.