Are GPUs the future of CPUs?

Kerrick Long is a geek who submitted the following question to me this weekend:

I’ve been thinking recently about the advances that chipset makers have been making with GPUs, and how the CPU market seems to be stagnant at the moment. Recently, ATI made the first GPU clocked at 1GHz available with the Radeon HD 4890, factory over-clocked. In addition, that same card has 800 stream processors, while most CPUs have only two or four cores. Those cards also use GDDR5 memory, consequently.

On the software side, Snow Leopard is integrating OpenCL into the Mac OS, allowing developers to harness the power of the GPU in applications that traditionally might’ve just used the CPU. CUDA from NVIDIA also allows C programmers to harness some of the power of their GPUs with the right compilers, wrappers, and drivers.

All of this combined makes me wonder if someday soon we might see the death of the CPU as we know it today, to be replaced by a closer relative of the GPU. If GPU clock speed caught up with CPU clock speeds, the benefits of parallel processing available to the GPU would be immense! I know that changing architectures on an OS level would be quite a task (considering that Microsoft and Apple are just now making the switch from the decades-old x86 architecture), but do you think it will happen? Could the CPU be on its way out the door?