FPGAs are lovely.
And to be honest, a future PC with some kind of FPGA board on could be excellent for the gamers (and serious propellorheads) out there.
The game needs some physics coprocessing? No problem. One data transfer later, and the FPGA is a physics coprocessor.
Music program? Well, how about a quick switcheroo and that little chip starts doing DSP work.
Buy a FPGA that's big enough, and you could tell it "be a GPU". Lo and behold, you have a GPU.
Or if you really want something awesome, a 555 timer!
So it's not like GPUs are ever really going to wipe FPGAs out. Different beast, different application. Plus you can't tell a GPU to be an MP3 player with integrated storage and signal processing, like you can with a (large enough) FPGA.
Should really name them ACME chips...