The same thing that happened with the separate CPU/FPU years ago is gonna happen with the CPU/GPU.
Soon, there will be AMD CPU/GPU (and then there were one chip to rule them all) combo-killers' you know its comin', hence why Intel is "following" suit, with its CPU/GPU too, Larrabee.
This CPU/GPU meld (16 cores of GPU's and CPU's in ONE chip) inside a the future Net/Lap/Note-book, will finally usurp our big old gas-guzzlin' "chained-to-a-desk" PC, specifically in price per performance. "Specialty" servers will otherwise still exist in one form or another.
By then, both our present CPU's, and GPU's will be dead. It'll "ALL" just be parallel-processor(s) talking to "everything" virtually and simutaneously, again, in many forms, electronically, bio-neurologically,..., quantumly.
Of course, by then, we'll just be starting to populate other habitable planets within our galaxy.