Can't really comment on the quality of Guild Wars 2 since I am not really an MMO player. It's Torchlight 2 for me by quite a long way. It exceeded my expectations by a long way, they really nailed the action and made the grinding, builds, loot grabbing all fantastic fun to do. They were also really sensible with their design decisions, adding flexibility and convenience without fucking up the overall experience. It was exactly what I wanted, the Diablo 2 feel with updated aesthetics and modernised design without any "twists" to screw it up.
XCom is on my list to pick up but I haven't yet so I can't comment there. Terror from the Deep was the one I played the most in the past and that was great so I might end up loving it. The streamlining of equipment is offputting but there's no denying that the YouTube videos of missions and multiplayer make the combat look like a whole load of fun.