I wouldnt be surprised if it was budget related. Upper management saw the success of WoW in WOTLK and has been comparing each following expansion to WOTLK's success and reacting accordingly. Then take into account how old the company is, how successful it has been in the past and you know for a fact its bloated from the top to the bottom. Then, from what it sounds like to me, they pay low so they can hire another person onto the team down the line. So now they have 4 under paid dev's instead of 3. But thats factory line work thinking, in that a high salary can attract some extremely skilled coders that will run circles around the 4 devs willing to take a job at the low salary.
In other words - the only way we see WoW get back to enjoyable state will be to see the company fail entirely. Then a different, lean, well oiled machine of a company pick it up. We'll probably see rehashed assets on the first expansion from them and if the game still has legs, they'll probably knock it out of the park on the second expansion by them.
Either way, I think WoW has definitely fallen from its Throne and Im just waiting on it to be excommunicated.