I know that this is just an estimate, since we're just entering the first wave of games. I just bought my i5-3570k and 7870oc a couple of months ago. I figured it would last a while since that setup can run max settings on most of the games I play.
Now, I read that even COD, BF4, and Watchdogs recommends an 8 core cpu with a 3gb ram gpu. I have a 4 core and a 2gb! I planned on getting a PS4, but money is very tight right now. I wouldn't even mind playing on low-mid settings for the next couple of years. The earliest that I could upgrade would be a year and a half from now.