haha well I think you'd probably get an average of 60-70. CoD4 is amazing. I love the graphics engine it has. I have a 8800GTS and I get about 50-60 fps.. i really don't think I have ever lagged in that game, and I have max settings
I was referring to the guy with the 300fps settings.
As for AA, it depends on the resolution and monitor you are running.....also it's subjective. I usually think 2-4x AA is sufficient and I'm running 1680x1050 on a 22'' monitor