I wouldn't rule Utah out in terms of how good they are. Boise State? I dunno. I think Utah is for real though. I've seen quite a few Utah games this year and they look pretty good. Defensively, I'm not sure how they'd fare against some of the teams out there (Cal, USC, and Auburn have a good offense/defense balance and would give them tough matchups), but offensively they're very tough.
In terms of a playoff, the whole thing stinks. A playoff system is the right thing to do, but the greedy powers that be in the conferences and the NCAA won't let it happen.