O'Brien would have got an NFL head coaching job this offseason. It's not too often that a guy chooses a college job over an NFL job. From the start PSU has focused on a lot of NFL coaches, starting with Munchak and then moving to the OC's from San Francisco, Green Bay, and New England. PSU appeared to choose O'Brien over the other 2 and I wouldn't be surprised to see the Green Bay OC end up with an NFL job.
Notre Dame took an OC from New England, so why not Penn State ?( I know it didn't work out for the Irish, but the point is they took a similar type of guy, a hot OC from the pros)
One real challenge for O'Brien moving to college wil be that the New England offense is insanely difficult for wide receivers and he has no prayer of implementing it in a college setting. In just the past 4 years, the Patriots have let go of 2 high draft picks (Chad Jackson and Taylor Price) because they couldn't pick up the offense. A few years ago, Joey Galloway couldn't pick up the offense and this year Chad Ochocinco has been unable to pick up the offense. Essentially the wide receivers have to make site adjustments on their routes which means they have to be able to read coverage at/after the snap and run the route that corresponds to the coverage.