I think that makes sense, and I think it comes from two things: the relative strength (aka parity) in the middle of the pac-10 this year (besides stanford, there wasn't a single "bad" pac-10 team) and their strong non conference schedule.
Oregon played OU; usc played ND, Ark, and Neb; ucla played ND; stanford played ND; cal played tenn; oregon state played boise st.; arizona played LSU and BYU; washington st played auburn; UW played OU.
That's much stronger than any other conferences non-conference schedule. it's not like the big 10 where Mich plays ND, and OSU plays texas and that's it. it's across the board the conference plays tough schedules. i think it comes from a few years ago when everyone said the pac-10 was weak, and wanted to discount USC from the NC game. they ramped up the schedules following that. and it worked, i'd say.