I'm bored, so here are some scenarios for top ranked teams to get to the National Championship. Basically, what has to happen for teams in the hunt to make it to the big game.
This is pretty simple: win = in. If Bama beats Mississippi State, Auburn, and #4 Florida, they're in the title game. If they lose to MSU or Auburn, they can still make it in by beating Florida. However, losing to Florida might knock them out, as it would probably put Florida into the title game. Unless, of course, Florida loses one of its remaining regular season games beforehand. So maybe it isn't so simple. Alabama is one of the few teams that controls its destiny. It's also one of the few teams that can lose and still make the title game.
2. Texas Tech
Same deal as Bama, win = in. But they also have a tough game ahead. Oklahoma hasn't lost in Norman since September 3, 2005. That's good for a 23 game home winning streak. But if Tech beats them (and Baylor), they might be able to lose the Big XII Championship Game and still make the National Championship. Of course, if they win their conference title game, they're shoe-ins for a title shot. If they lose to Oklahoma, things get complicated. BCS rankings would be used to break the three-way tie in the Big XII South, which would probably give Texas or Oklahoma the edge. They'd likely go on to play in the conference title game, and barring disaster, the national title game, as well.
Texas needs some help. They need Texas Tech to lose. The computers have Texas #3, but the USA Today has them at #5. If Texas Tech loses, Oklahoma would likely leapfrog Texas in every poll. Then again, the computers might push Texas forward. It's unlikely the BCS would choose two teams from the same conference for the National Championship Game, so the help Texas needs would have to come from within the Big XII. Texas loses in tie to Texas Tech, so they need the Red Raiders to lose twice OR for there to be a three way tie in the Big XII South so the BCS can be used as a tie-breaker.
The Gators will probably get in if they win out. It won't be easy with #25 South Carolina, #19 FSU, and #1 Alabama left on their schedule. But if they win the SEC with 1 loss, they'll be in the title game. Then again, the BCS might select a pair of Big XII teams. Florida cannot get into the big game if they lose.
The Sooners might be in better shape than their #5 ranking would suggest. In fact, they might not need any help at all. If they beat Texas Tech, then Oklahoma State, they'd likely force a three way tie in the Big XII South. The BCS would be utilized as a tie-breaker, and with those quality wins, they'd likely receive the divisional title. A win over the Big XII North winner would make them Champions of the toughest conference in football, and the most likely selection for the National Championship Game. They also have one major advantage of Texas and TTU (should they beat TTU, of course): their loss came earliest. The pollsters have had more time to forget their defeat.
The Trojans need a great deal of help. They need Oregon State to lose in order to claim the Pac-10 title. Then they need Alabama to lose twice AND Florida to lose. Or, they need all three of the top Big XII teams to finish the season with 2 losses. Even then, they might not get in. The computer ranks them 8th, their 35-3 win over OSU is a distant memory, they lack numerous big wins over top teams, they lost to Oregon State.
The Utes have next to no chance. All the BCS conference teams ahead of them would have to finish with 3 losses, as would Penn State. Then again, the computer has them ranked 4th.
8. Penn State
The Nittany Lions choked, plain and simple. You can blame the wind, but it was a choke. Teams like Penn State are talented enough to beat teams like Iowa on the moon with no oxygen. How does PSU get to the title game? Like Utah, they'd need everyone to lose 2 or 3 times. Technically, they still have a chance, but not much of one.
Prediction: Oklahoma and Alabama win out, meet each other in the title game. OU wins 20-17.