JAYDEEJOHN :
Dont forget, people will defend the use of physx, CUDA etc, and be willing to pay that extra
No no no no, I truly have to admit, as sad as it is for me to say I have actually bought a Sapphire 5850 to replace my 9800gtx+..... The 5850 is a beast and can play Crysis on Very High settings and 2x AA with 35plus fps on my PC and it works great, blah blah..... I do have to say, even my older, (come to think of it, way much older g92 architecture) 9800gtx+ felt and came out better in terms of Physics due to PhysX. I will tell you that upon throwing barrels, koreans, shooting trees, turtles, birds, and water, Crysis with PhysX is much better. This is comparing a 9800gtx+ to a 5850!!!!! Unfortunatly Toms and other websites do not compare physics, lighting, color palets, shadows, shaders, textures, fluidity, bump mapping, or whatever in terms of small details in their comparison charts understandably because there would be too much to report and differentiate.
However if you have two PCs or if you change your GPU and compare these details like physics, color, you will see that Nvidia does however have a better physics system. I can swear by this as you can feel the difference in the game. That is once positive thing that a beautiful game like crysis can give gamers and testers, its programming and use of physics, cpu's gpu power and AA....