A lot of things. First, the SEC is locked into their TV deal for the next 12-13 years. The PAC-10 has a deal that expires in 2012. So it's entirely possible that, after turning it into the PAC-16, they'll sign a more lucrative deal. Second, by joining the PAC-10 and not the SEC, they're guaranteed to stay at the top of the conference food chain. Florida, LSU, Georgia, Alabama or USC(on probation), UCLA, Oregon, Stanford? No brainer. Third, and this might be kind of hokey, it's been muttered that the SEC is less academic than the PAC-10. While this may be true, I think it has zero influence on their decision.