I'm not sure everyone understands what these numbers mean. Intrade, Nate Silver, this guy. This is just the likelihood that Obama will win the 50/50, win or lose. 75% chance does not mean the same as receiving 75% of the votes, or the EC or anything. I had another online discussion today with someone who couldn't figure out how the race is only a few points in Obama's favor, yet Intrade shows 67%.
If Obama wins by 1 electoral vote, then they win the bet.