While I'm not an MMO fan, I don't agree that Guild Wars 2 is "why not buy WOW instead?" territory. No subscription fees - you'll recoup the investment in 3 months but can play indefinitely; it's prettier (in my opinion), and has quite a few mechanics that are quite different. There are many MMOs that are"might as well get WOW", this one isn't really. Though, of course, it still *is* an MMO.
That said...Well, I'd buy neither. but that's personal taste. There are "better" games out there, especially bang-for-buck-wise, than a pre-order (have you played GTAIV with all its expansions and mods? have you played Saint's Row III and V? they're all cheaper, offer a great game without patches and day one server issues and the like, etc).
Have you tried, and I'm just throwing shit around to see what sticks here, considered the Two Worlds pack? it's $5.99 (or whatever, Steam's conversion rates are completely incomprehensible) right now, the first one's a great RPG, the second one's pretty neat as well, I haven't honestly played the expansion to the second nor the tower defense game, and it'll have you set for 50-60 hours of entertainment for a fraction of the price of either of your choices.
Of course, if you are looking for the social aspect (gah brrr) offered by those, I simply don't understand how your mind works and can't make a good suggestion
but I'd imagine there're other games people on this board are playing which could offer that as well.