They'll run most everything out there at Max settings, Give or take AA Levels/Modes, at 1080p just fine above 60FPS.
The problem with this question is we dont know how much Grahpics Technologies are going to advance in the next 3 Years.
If your bored, go see how a GTX 580/590 is performing in modern games, Those Cards are 3 Years old.
144Hz vs. 60Hz is more about feeling then visuals. imo