By now I suppose all WoW fans have read the news about the new expansion, so no need to paste here details. I feel Blizzard is hammering the nails on WoW's coffin, at least in the western market. Pandarens were always a little joke in WoW universe, and now become a playable race and theme for a expansion. Very, very disappointing.
You've been running around Kalimdor and Eastern Kingdoms, then Outland and Northrend, thwarting the plans of the big baddies, following a good chained history and then... everything goes to a halt and something new is introduced, disrupting totally the chain. By that time Deathwing will be just a dead husk, but what about of the threats still looming around? Old Gods, Burning Legion... they aren't going to kick back and relax while we're in Pandaria learning kung-fu!
WoW subscribers have been going down since Cata was released. Almost everyone felt the expansion didn't bring anything really new that was worth to keep playing the game and went away looking for greener pastures. In this case it seems Blizzard considers american and european markets dry and looks to attract a raising market like the asian and specially the chinese, focusing the entire expansion on chinese lore. Will it work there? Probably. Previous expansions, specially Wrath of the Lich King were hard to be introduced there. Chinese specially find undead and skeletons very disgusting, a taboo. So an entire expansion based on creatures they dislike wasn't going to work (Blizzard had to change several mob models for the chinese version). So they're now fully betting on the chinese market with something they like. I wouldn't be surprised if after Mists of Pandaria we get Sands of Arabia or Snows of Caucasus as the new expansion.
But at least, one good new (and also a good hook to keep playing): if you commit to one year of WoW gameplay you get Diablo III for free. A good marketing trick to secure player base.