That's not really that much graphical prowess, compared to the other consoles. 3 CPUs will help grind out the game logic, but graphics-wise, it's just there for show. I don't know how much they plan on gaining by having three, really. Having two in the latest Macs doesn't up the speed a huge amount unless the app is so optimised it hurts.
Then again, you americans like just adding more to make things look better
