The problem is with the bowls though... if you keep expanding the playoffs, the attendance at lower ranking bowls might be worse than it was this year.
You need to reward a regular season, but does it have to be "perfect" like many think? As we saw this year, a team like Stanford could kick some ass. Guess what, the 2009 Hawk team could kick some ass too. Nobody would've wanted to play that team, just like nobody wants to play Stanford again this year.
I'd have no problem with expanding it to 8 though. Why not?