The Big 12 adds TCU, and Oklahoma goes to the Big 12 North.
Why add Oklahoma when Oklahoma State is the northern-most South school?
If we're going to do away with geographical logic, then it's time for a massive overhaul of alignment.
The article states that if CU were to leave, BYU would be the likely candidate to fill their slot in the Big 12. That seems odd to me considering the distance. Colorado State would seem a more logical choice in some ways, but is CSU really too small to carry their own weight in the Big 12? (TV sets, enrollment, revenue contribution, sports competitiveness, etc.)
Colorado State does not have the facilities, resources, or financial backing to join the Big 12. They're struggling just to keep up with the schools in the Mountain West.
Colorado and Missouri appear to be the two most likely candidates to leave, which is probably why they're always the ones discussed whenever this topic rolls around again. They each have a "natural" geographical fit with another major conference.
TCU would be an obvious candidate to join the Big 12. People like to throw Arkansas out there, but I don't see any way they leave the SEC. Memphis could be an intriguing option, especially if the conference wanted to move to an East/West alignment. Memphis would be a nice, if not huge, TV market to bring into the conference.
Texas' desire to leave the Big 12 will always be complicated by the other Texas schools. Remember that the only way the Big 12 was allowed by Texas politicos was by including Baylor. aTm, Tech, and Baylor have enough clout to probably ensure that Texas doesn't leave them screwed with the remaining Big 12 schools.