I think some poeple are missing the point about GPU-based physics: physics simulation/collisions can probably be done in the vertex pipeline ...perhapswith the next generation of cards/directX.

In the meantime CPU-based physics are great as it is--look at Crysis, this game has amazing physics, and I'm pretty sure it either runs on the CPU or GPU.

This would eliminate out any need for an additional physics processor. The fact is, this isnt about whether consumers will buy a physics processor, but whether its really a good idea in the first place. I think not.