Don’t bet anything on JC being on the ticket. It wouldn’t help anything anyway - JC’s not from a swing state, and blacks aren’t going to vote Republican because Obama’s going to be the Dem nominee. (He’ll be the next President, too, if McInsane gets the nomination.)
Actually, JC would give Mitt a lot more credibility with the southern Christian conservative voters. I wasn’t worried about picking up the black vote, which is a near impossibility regardless. JC would have more appeal if he was from a swing state, but I think he would offset much of the negatives of Mitt being a Mormon northeastern GOPer.