There is no doubt that WoW will always be looked at as one of the defining MMOs to ever hit the gaming world. Love it or hate it, there is no denying its impact on both computer games, and main stream culture. As great as a game WoW has been, I can't help but think "Now what?"
With the announcement of Wrath of Lich King expansion the game feels like it has come to a bit of a stand still. In my opinion the announcement came far too soon. I understand it was Blizzcon, and Blizzard wanted to make a splash, but I do think it was a bit unfair to the players.
Expansion announcements always have a way of slowing the drive of many game players. It's hard to motivate yourself to work toward items that will be rendered obsolete by future quest items and random drops. This was made evident when the Burning Crusade expansion was announced. Game advancement came to a halt. Remember Naxx? Count yourself lucky if you do. How many folks even stepped foot there, let alone progressed through it. Both The Black Temple and Hyjal Summit face the same danger as Naxxamaras, two great well thought out and designed instances that most players will never see.