The Fort Worth Star Telegram mentions that Louisville and BYU were the 2 teams being considered for expansion before the Big 12 ulitimately decided to hold off. What is more interesting is the fact that they mention Florida State and Clemson showed interest in at least talking about a Big 12 move during that time and again, the Big 12 said "no thanks".
Now that they are in panic mode, will they call FSU and Clemson and beg them to engage in talks? It seems far fetched at first, but in a world in which Missou and A&M will bolt one power conference for another, there's recent precident to show that at the very least, it can happen.
Who knows how much validity there is to that speculation, but it doesn't sound like great news if you're a BYU fan. Utah got in to the PAC because Texas decided not to make the switch and the conference needed a team to add with Colorado. If BYU get's in, I expect the situation to be similar. You're going to need a few people to tell the Big 12 "no". BTW, there's no shame in that. It doesn't matter how/why you got invited to the party, as long as you're there.