The hardware certainly isn't. We never got a good look on what's in the PPU.
Well a some insigth where put forward:
If NV wanted to push physx they could very well have released a striped down version of the GPU driver similar to how Tesla is run. They can even make windows not realise that it's a video card. Since windows can't really figure out what a device is for sure. As long as there is a suitable driver for it Windows will identify a device as anything the driver claims.
Dons't make much sense if you look at NVIDIA's upcomming architechture...from SP to DP and a lot of focus on GPGPU (which physics is)...one card with all the features, not 2 cards.
My only spectulation now is when they will (again) incoperate a "soundcard" on their GPU's...and promote their cards as "the only card needed for gaming".