I could see this on NFL and college football players in the future. Probably integrated into their helmets rather than having a camera attached due to the physical contact. However, there will be major problems that this will create. First of all, many extra curricular activities happen out of the eyes and ears of the public (example: players punching other players in pile ups). This might create push back from the players. Another thing is that opposing teams will have a much more in depth understanding of the schemes and play calling if enough film is made public.
I can see the NFL milking this thing to death in their deal packages. "New QB cam follow the action like never before with your order of NFL Sunday Ticket."
It makes more sense as a QB coaching tool than an ESPN camera position. You could walk a QB through his decision process while watching his head position. The NFL hasn't really accepted that the wire cam is a better in-game action perspective, so no chance they'll go this personal, though I think it might show up in the Pro-Bowl.
I think how BA it would be to watch the receiver tear through the line, get 20 downrange, WATCH the ball land in his hands, and then the green coming at your face and onto the lens as he gets plowed just shy of the in zone, soooo close, but just out of the VIEWERS reach.... You wouldn't be thinking "He's almost there..", you would be feeling "I'M ALMOST THERE!!!!!"