The real question is how long will it stay fun. My problem is WOW, while being the best mmo out, is still essentially the same shit, different day, unless you are a fanbois Blizzard lifer.
I like WOW, and it holds my attention longer than other MMOs, but I get bored pretty fast. I did the raiding thing for a while, but I guess I've spent too much time on the gerbil wheel. I played EQ for years and DAOC for an extended time, but the clone games afterwards don't seem to hold my attention.
Maybe Zennish is right, and I am old.