It's actually more than just money, but money is a big deal. Contrary to common (my) belief, Nebraska football is a prized commodity. According to Forbes Nebraska's football program is #4 on its most valuable list. In 2009 it brought in $93 million for a profit of $49 million. For comparison, Ok State's football program (which made more than Missouri) made $18 million. To further drive home the point Kansas' basketball program brought in $16 million and a profit of $8.3 million.
However on top of the money, there is an entire backstory about Nebraska and Tom Osborne in particular being unhappy with Texas so there's a certain glee for Osborne to stick the shiv into Texas - who preferred the Big 12 to stay intact.
What Does That Mean for the Big 12?
According to multiple sources....The Big 12 is finished. As in dead, dead. At last report Colorado is all but out the door and headed to the Pac 10. This is where things start becoming known unknowns. The Big 10 and Pac will fight over Texas, the crown jewel of College Football (profit wise) The Pac 10 will reportedly offer (in addition to Colorado) bids to Texas, A&M, OU, Ok State and Texas Tech to form a new Super 16 team conference. However there are rumors that the Big 10 will also make a push for a number of Big 12 schools. In fact they would push for Texas, Missouri, A&M, and Notre Dame - which might be enough to entice all as the profit possibilities seem fairly astronomical. So the short answer is the Big 10 and Pac 10 will start picking at the soon to deceased body of the Big 12
What about Politics?
This is where the unknown unknowns start. That's the political realms. For a number of reasons the Texas legislature/Governor have some influence on where Texas goes. There will be significant pressure to force the Pac 10 or Big 10 (or SEC) to include a package of schools with Texas (i.e. if you take Texas you have to take A&M and Tech) The deal breaker might be if they chain Texas to Baylor (a very Conservative Christian school) in which case liberal leaning UC-Berkley might veto the entire thing if they have to share the conference with Baylor. Similarly it's unlikely for the Big 10 to accept Texas Tech give its poor academic leanings. So it's possible the Big 12 will limp along but more likely someone will back down and Texas will leave - thus ending the Big 12.
What is My Guess at the Future?
At almost every turn in the expansion process, the almost unthinkable turned to possible turned to reality so making guesses is hard. If I had to guess I'm guessing that UT will uncouple itself from Baylor and alongside Tech, A&M, OU, and Ok State will help make the Pac-16 a reality. As to the Big 10, Jim Delaney (Commissioner of the Big 10) has said expansion will go in phases. Phase I is Nebraska and a conference championship game. If the Big 10 get's the right teams it's entirely possible it'll expand to 14 or 16. Notre Dame/Texas tops the list but Missouri, Rutgers, Syracuse, Pittsburgh, and Maryland are possibilities. If I had to guess it's all on Notre Dame. If Notre Dame joins the Big 10 will balloon up to 16 (if only because the threat of ballooning will be the catalyst to Notre Dame joining) if ND says no...the Big 10 will stay pat....for the time being.