The Big 12 has dominated, going 27-3 non-conference, including 6-3 against the other majors and no bad losses. The SEC was strong at 42-6, although most of those wins came against Sun Belt, MAC and 1AA opponents, as usual. Very few road games, a bunch of close wins over bad teams where there was questionable officiating, mostly par for the course stuff with the SEC.
The other 4 leagues are pretty tightly bunched. The Big East went .500 against the ACC, as it does every year, and 5 of the 6 games were decided by a TD or less. SDSU, Boise, UCF, SMU and Houston went 4-3 against the majors. The SEC has pulled away from the pack on the backs of a couple of programs, lots of home games and biased officiating. most years everyone else is in a pretty tight range.