Eh, I think it's easy to read too much into wins and losses this early in the season. Even the conference challenges -- I've seen them go every which way and the correlation between the results and actual conference strength seems loose. A few years ago I recall that the Big 12 beat the SEC soundly, something like 8-2 or 7-3, despite the fact that the Big 12 was by no means a strong conference that year.
The Pac-12 has some teams struggling with either injuries (Oregon, UCLA) or just young rosters that are far from their season ceiling. It'll all rise to the top over the next few months.