My GT240 plays most games I throw at it (although I can't use high settings). It was not able to play Battlefield 3 though, so any game in that category, I wouldn't expect it to work. But the 280 is better than my 240, I don't know the difference though.
I play Skyrim, NBA 2K13, Assassin's Creed, etc... I haven't tried Creed 3 yet but I'd expect it to be playable.