A little bit of a surprise, but USC will be able to keep its 2004 AP title, though it is extremely likely that they will lose the BCS title. As much as I dislike USC's football program, I like the logic employed by the AP. FTA
The poll is intended to measure on-field performance. If teams are allowed to play, they're allowed to be ranked and USC certainly played in 2004.
This is a similar sentiment that I feel should have been applied to the Brian Cushings defensive POY award revote after he was found guilty of performance-enhancing abuse - the records might be wiped clean, but the games were still played and USC won the title in 2004. Strip them if you want and put a big asterisk, but nobody will forget that they were probably the best team in America that year, and employing revisionist history just seems like a PR stunt. Same with the call for Bush to lose the Heisman - he was still the best player in college football that year, so make a note in the books and just let it go.