Romney/Bachmann Ticket
A VP choice like that, and Romney throws away his shot at becoming POTUS. I think he is much smarter than that. He won't pick any of the opposing candidates as a running mate, assuming he wins the nomination, and that is definitely not yet a given. My guess is that he at least tries to get Rubio on the ticket. Rubio might bite if Republicans can convince him that without him on the ticket, they probably lose the election.
Rubio might go for a Romney ticket. But I am thinking Pawlenty or Huntsman.