Michigan missing PSU actually hurts Michigan... PSU was once a powerful program, but not so much anymore. It's fun to joke about Michigan "ducking" a "traditional" power, but the reality is Michigan would beat the crap out of Penn State. For whatever reason, Wisky plays OSU tough, but Michigan usually smokes the Badgers.
I don't mean this as a slam or anything, but I think if you look back over the last 10 - 15 years you'll find that Michigan is often over rated going in to the season. Back in the mid-90's it was worse than it is now... Seems to me that pollsters have a handful of teams that they immediately put in the top 10 despite what might have occured in the offseason or what positional losses have occured.... Some of those teams are: Michigan, Florida State, Miami, Oklahoma, Texas... Again, I'm not suggesting that these teams suck and dont deserve to be rated or the like, but I don't think pollsters give a critical analysis of these teams year in and year out, but rather just assume they're gonna be good. Nebraska used to be the same way, until it became obvious that the wheel's had fallen off.
This year is a good example of my point...
Michigan lost their starting QB and Heisman finalist RB ... What do the preseason mags say? No big deal. This happens all the time.
Ohio State loses their starting QB and best WR - What do the preseason mags say? Woa nellie... Ohio State will have a tough time replacing all that talent. Look for a solid year, but national title aspirations are foolish.
I'm generalizing a bit (and yes, I realize both UM and OSU lost more than just two players), but I think if you look back you'll see this "pre-season" trend plain as day.