With GW2 having been my very first MMO, then moving to WoW at a friend's request, seeing how Wildstar does things was pretty much what I've been trying to find in an MMO. Active combat, a trinity, housing, mounts, interesting PvP that won't 100-0 (hello gw2 thieves!) you if you have enough awareness to get out the way of that big pulsing box of doom, and extensive and challenging PvE content that didn't require doing the same thing on different difficulties (the grand LFR, Flex, Normal, Heroic shenanigans) or grinding gear to get one-shot slightly less often (hello fractals) was something WoW and GW2 didn't do, or do well enough for me at least.
That, and while I love GW2's buy-it-once, I don't mind paying a sub or saving gold to pay for the month. Wildstar also looks like it won't be overrun with race bias that messes with the faction conflict (at least not now).
So far the only thing I don't like is the whole Elder Gem thing(and overly sexy female models for the non-human races, gw2 did that right at least), but after a 50+ page thread of players discussing how it's not going to be a good thing to have a 10-month time gate tied directly to character progression, the devs have showed that they really are listening.