It's been a while since I've really gone looking, when when I had everything has looked pretty dead (Alliance side has looked dead for a long time, and now it looks like Horde is dying too).
I could be wrong, maybe I'm not looking in the right places.
I've been told there are still RPers, but from my experience, it's all been very clique based. If you're not one of the bros, so to speak, you get ignored or pushed out. Perhaps I just have bad luck.
Then there is also the question of the quality of the RP. I don't mean to sound like a snob, but, I'm not thrilled by the idea of RPing with god-modders or vampires, or any sort of mythical hybrid that doesn't exist in the game.