Teraminer, just grab your cell phone and shoot some video of the FPGA in action. If you have one running it shouldnt take 10 minutes of your time. That should be good enough proof to assert you are not just trolling. In theory, it could still be a more elaborate hoax, but I kinda fail to see the point in anyone doing that.
maybe he doesn't really have a real prototype running yet, it's all in the brains.