The i7-4770k will last longer, assuming that game developers start taking advantage of the hyperthreading. Still, I'd pick the i5-4670k. You'd get similar results for 3 years, and then you'll want an upgrade anyway. Maybe to a nice 16-core running stock at 5GHz, we'll see
OK, I have a 4770k myself, but I do a lot more than gaming on this PC.
will the i5 4670k last a few years before it bottlnecks gpu's
Even if it does you will still be able to play games.
My nearly 6 year old Q9450 is still quite capable of playing modern games as long as expectations are not too high. I can pretty much play Skyrim with very high settings, the HQ texture pack and other high resolution textures and many other mods. Along with my Radoen HD 5850 I basically can get between 50 - 60 FPS @ 1920x1200 resolution on my 60Hz monitors (which limits the max FPS to 60). I'm sure if I had a more powerful GPU I could max out at 60FPS even if the Q9450 were to bottleneck it.