The same thing happened to me going IAH-SFO-LAX for the National Championship game for the 2009 season. There was a medical emergency that diverted the plane to LAX. About half of the plane got off, all proudly wearing their burnt orange. Luckily for me, and most others, the only reason we were making that flight was for the game, so it was a 3 day weekend, carryon only type of trip. Didn't have to worry about the luggage.
Only got mileage for IAH-LAX, not for IAH-SFO-LAX.