Yes, ARM because Intel won't license x86 to Nvidia.
Call it a blessing in disguise. NVidia is poised to take a serious bite out Intels sales in the server/super-computer market, if they can pull off superior performance thanks to CUDA/openCL, their integrated GPUs, and a relatively low power footprint.
What nvidia seems to be lacking for a complete revolution is desktop support, which is quite married to x86. While Apple OSX and Ubuntu may be able to quickly ditch x86 in lieu of an arm core, the majority of users are running Windows which is x86 only. I also have serious doubts about Win8 success unless it still somehow offers legacy app support on ARM.
Assuming that they'll get the performance piece right (hey, it's nvidia) all of this hinges on backwards x86 compatibility. If nvidia is smart, they'll temporarily include functionality to translate instructions tearing down the last remaining wall for serious market proliferation.
As a linux user, I'm *really* looking forward to this. Something tells me that in the intrim, nvidia will be pushing support for Android and Linux as systems for this new processor -- only speculation, but there you have it.
