After the first year of barring race-conscious programs at public universities in Michigan, the local press has begun to examine the fall-out. Basically, the stats are mixed, but the upshot is that minority enrollment shifted to lower-ranked schools, and higher ranked programs are having trouble attracting even qualified minority applicants because their scholarship programs also had to be discontinued. One interesting outcome (though it might be statistical noise) is that minority enrollment dropped even at schools that did not previously use race conscious admissions procedures.
Also, interesting article given the topic: Richard Lempert, David Chambers, & Terry Adams, Michigan's Minority Graduates in Practice: The River Runs Through Law School, 25 L. & Soc. Inquiry 395 (2000). Basically, it surveyed the history of minority Michigan law students admitted under affirmative action programs, in terms of their success after graduation. The results? Under every metric measured, these students performed equal to their White peers.
But remember, they weren't qualified to be there.