A friend of mine flies quadrocopters and other aerial RC shit and he used to have a GoPro of some kind.
He recently bought a Sony HDR-AS10 or 15, I don't know which, and he seems happy with it. Apparently there's free firmware out which allows 60 fps at 1080p too.
http://www.youtube.com/watch?v=gpAAyttYUzsIn light of this it seems to me that GoPro is just living off of the hype and brand recognition at this point. It just seems to be the name that springs to mind when someone says action-cam.
Note that I don't know shit about cameras so I could be wrong.
Attached image is NOT shot with any of the aforementioned cameras afaik.