Tony Jefferson and Kenny Stills have decided to announce their collegiate choices together on December 18th, but according to scout.com, neither will choose Michigan. Both players were at the Michigan-Ohio State game, and both came away with positive reactions to it.
Stills is apparently to choose between Oklahoma and Florida, whilst Jefferson likes Oklahoma and USC. If this is the case, I think they will both pick Oklahoma, as they are rumored to be a package deal.
Although these prospects were both longshots for Michigan, I find it hard to believe both have ruled out UM. There will be a press conference with video of the event, and if they do the whole "hats" thing, I wouldn't be surprised to see a Michigan hat up there, even if they don't choose it.