Like a dedicated physics unit?...can't say i've heard of that on the 8800...But with advanced directX10 shaders, physics should definitely be better. I doubt that theres a ageia like PPU fused in there.
As GPU architecture get better, physics processing will get better too no doubt...
And if the 8600GTS beats a 7900GT, it will definately push past a 7800..
Great mid range cards.