If the way they've been begging Michigan hockey fans with e-mails, Groupon deals, etc... to buy hockey tickets the past few seasons is any indication, then I feel this is only the beginning for football attendance woes.
Hockey used to be an guaranteed sell out with massive waiting list every season. But years of increased ticket prices + horrible home nonconference schedules + b-ball comeback drove fans away (and, of course, the past two seasons haven't helped matters though attendance was declining before that happened). They finally fixed the horrible schedule part this past season. Now they need to win some games again.
But it's the same story for football... high prices + struggling team + horrible home schedule is a recipe for no one buying tickets. Winning can cure some of the problems, but at the end of the day, for the price they're paying, fans want to see high-profile teams play at Michigan Stadium, not Jerryworld. I don't see attendance woes getting better until they play a home schedule that's worth forking over the money.
Call it a bit of a fan revolt, but with more folks living on tight budgets these days, I don't think fans are going to just give the university their money freely and take whatever they feed them as opponents anymore. But maybe that's what it'll take for the athletic department to get the message.