There are really three key components that snowballed this whole crappy realignment.
Straight from this blog, cornation.com contributes a lot of the reasons for the move becuase of Texas. Nebraska went from being the powerhouse of the Big 8, along with Oklahoma, to a reduced and minimal role in the Big 12. In addition the Big 12 championship game, as well as the headquarters are in Irving. The bottom line is Nebraska officials are pissed off at Texas, because they control everything & get all the attention. That's why they decided to leave & that's what started the domino effect which is sure to forever revolutionize college football as we know it. As, as a sub-caption blame, Nebraska is too.
THE BIG 10 & PAC 10
Jealous and angry about not being able to compete with the other major conferences and feeling left out, they planned this a few years back. The SEC, BIG 12, & ACC, all had 12 teams and were gaining the spotlight, especially & they felt left out. So they had two options, expand or playoffs. They tricked the Big 12 into rejecting the notion of playoffs, so they could set this up for the future & they have. Though this argument is not my own, I agree with it. I read it in an article from ESPN & it's probably true. So you can blame them for this. Another sub-section of blame goes to money, because that's what this move is all about $$$.
This is more an analyzation of history & my own opinion, & could be argued as b.s. or factual. But in 1991 the SEC took Arkansas from the Southwest Conference, which held the what is comprised of the Big 12 South today, with the exception of OK & OK St. 5 years later, the conference disbanded & created the Big 12. This would create growing dissension between Texas & Nebraska, as well as the South & the North, where the South got all the attention. By creating these two powerhouse conferences, the ACC joined in & now the Pac 10 & Big 10 feel left out, so they're gonna screw everybody else & the sport to compete & for the mula.
Therefore, more than anything money or gree rather, has ruined college sports.