I do not think they are puting enough effort into MoP for how much money they rack in each year. Hell even each month. I mean think about it. 10 million times $15 each month.
I realize they also have to pay for developing Titan & the next WoW expac(s), plus pay all the employees. But even as an optimist I am feeling like we are really getting skimped on content (5.2 does not look particularly exciting to me, dinosaurs and rehashed terrain/mogu architecture. the map of the new area is pretty small as well).
But at the end of all of this, I would like to say I've played WoW since 04 and I still love it