Solid pull for the Wolverines. Definitely carries some measure of risk in terms of him being a successful NFL coach and possibly wanting to go back or at minimum being a candidate for every open job each season. But the name alone will do wonders for recruiting. So if nothing else, he'll set them up very well in terms of talent.
And I agree with Ox that Meyer will be Meyer, and have success regardless of who's in his conference. But I do think it balances things out considerably in what has been--up to this point--and OSu league, with Msu being a minor factor. That changes now, which will be kind of nice.
All that said, anyone who leaves the Bay area for Ann Arbor, alum or not, should be checked for mental stability. You're already rich, so money's not that big of a deal. Or perhaps this just sheds some light on how awful the SF front office is to work for. Either way, it's a pretty big coup on the part of UM.