I have got my eyes on a 780. I don't really know why. I barely even game
Steam says I played 10 hours of Company of Heroes in 2 weeks. Which is, uhm, an old and undemanding game.
I like the idea that I can play any game that comes out on max, though. Inevitably I will get Battlefield 4, the new Metro Last Light. I am also anticipating much better looking and therefor more demanding games once the new consoles arrive.
My i7 2600 may even bottleneck a 780 but I hope not too much. If it does, I guess that will need replacing further down the line too.