Personally I don't really care
I can't really stand MMORPGs, least of all WoW or Guild Wars. It's not just the fact that they're only RPGs in the sense that you can choose to be a certain race or class, and don't really give a sense of playing any kind of role. It's partly the fact that you do basically spend the whole time running around in a Diablo-esque hack n' slash trying to level up the whole time and trying to find better gear. I'm sure some people find it fascinating, but I would only ever pay a one-off game fee for it, certainly not a monthly subscription. I also can't stand the people - in Guild Wars, if you go to a town, it's mostly full of people running around saying 'Join my guild! Join my guild! It pwns!' and other such inanities. How you can even vaguely immerse yourself in it (and I'm no D&D obsessive) when there's annoying Americans/teenagers running around making stupid comments and doing vaguely-funny-the-first-time dance moves, I've no idea. Give me single player any day.