If there's an open beta to confirm my desire to play it, then immediate. Otherwise, it depends on when I get to see a significant, unedited period of gameplay.
Hm, actually I'll probably get it for christmas, and I'll still work a couple days a month, so that should cover my monthly fee. There, a new plan has been forged!
If WoW does get released mid November imagine the overload on the servers that thanksgiving weekend. Most of us would be better off eating turkey and stuffing.