From Camel at Sea on Shaggy:

If the TV money dries up, or evens out on a more permanent basis, then the Big 12 should try to lure Mizzou and Arkansas away from the SEC (where neither are a great fit culturally, historically, financially, or geographically.) I think you could make the argument that the SEC is bad for both competitively, too. Both schools fit the Big 12 in all of those respects much better whether their respective fanbases would admit it or not.

If the TV money never really dries up, or evens out, then the Big 12 probably breaks up at the end of the current TV deal.