I am not saying they were ranked number solely due to being in the PAC-10. I will assert that they have been UNDEFEATED because they are in the PAC-10. Three years ago, they lost to an UNRANKED team, while LSU lost to a top ten team. Also, three years ago, it was ONLY due to a missed chip shot field goal (can't remember who), that they survived without a loss.
USC has put up impressive offensive numbers against PAC-10 teams with VERY weak defenses. Arizona State, for example, is ranked 113th in the nation in defense. Some have suggested that the conference is ranked low in defense because there are several teams with high powered offenses. I disagree. UCLA had a terrible defense, but a very good offense. Oregon had a good offense and a so-so defense, and at 10-1 lost to a 7-4 team. The fact that the BCS did not include a 10-1 Oregon team in the bowl series in indicative of the fact that they recognize the weakness of the conference.
As for USC's non-conference play, they LOST (as far as I am concerned) to Notre Dame..only a very lucky fumble out of bounds, and a good spot for an offical saved they butts.
They did beat a terrible Arkansas team ( later in the year, Arkansas was improved after the coach gutted the team and replaced the starters with underclassment).
In a nutshell, USC has an easier road to number 1 because they play in the PAC-10.
Does this mean that I do not think them the best or at least second best...No. They had a great team this year..BETTER than the last two.
How did LSU's defense do vs. ASU this year?
"As for USC's non-conference play, they LOST (as far as I am concerned) to Notre Dame..only a very lucky fumble out of bounds, and a good spot for an offical saved they butts." Oh come on! Following that logic, Texas LOST to USC. USC got lucky against Notre Dame. Texas got a lucky call against SC. The difference is, the Texas call should have been reviewed -- there was no bad call in the ND game. (Actually there was a bad call against SC earlier that led to an ND score, but there was no bad call with the lucky fumble. The "push", I'll grant you, was open to a call.)