I think the first batch of quad cores were barely out 4 years ago :P
And dont forget, even if the game takes up just 2 cores, do you only run one program at a time? I sure dont :P
The Q6600 was released in 2006 and upon it's release people were saying that then just what you said earlier, that games
were all going to be using four cores. And yes I do sometimes only run one program at a time even though I'm using a Quad core.