I know more than one person who didn't have a deposit to leave so the hotel blocked that person's account from any charges - pay TV, phone, room service, etc. Not sure if that would be the case with the hotel you might get.

Last month I stayed at a hotel in Anchorage that I won through Hotwire months ago. Gave my credit card at check in for the guarantee and guess what? The hotel charged MY credit card for the room stay. Ugh! A phone call took care of it but it is not the first time that has happened.