Having just started playing WoW, pretty much yesterday (already have a level 21 wargen hunter), I can safely say that really, it's pretty decent. It's probably because I'm new and paid $10 to get everything up to but excluding the last expansion, and it may help that I have a friend to play the game with, but it really isn't as bad as a lot of people say. I could see long time subscribers being disappointed because, let's face it, everything gets old eventually. Nothing is eternally fun. The friend I play the game with has been an off and on subscriber for the past seven or eight years, sometimes taking up to eight or nine months off before returning for another two or three. It makes sense that the experience would get stale, especially when Mists of Pandaria wasn't exactly a stellar expansion.
For anybody that wants it to die though: from what I know, Blizzard wants to end the series with a return of the Burning Legion (as well as their final defeat, I imagine). They also have a new project in the works that, since they scrapped it in Spring and started rebuilding it from scratch, probably won't be ready for another couple of years. Just expect that once they announce an expansion that brings back the Burning Legion, WoW will probably be on the way out as far as active development goes. For when they will actually let the game totally die, figure probably another six years or so before it's private servers or nothing.
Of course, a year or two after the final expansion, once numbers start really dipping, they could scrap the subscription model and shift entirely to f2p. That would likely shock the system back to life as a profit generating machine via microtransactions for at least another couple of years.
