First off, I believe that each of the four soon-to-be superconferences will expand based on athletic value, media value, and academic value -- in that order. I say that athletic value comes first because each conference will take into account it's major strength. For example, the ACC and the Big East are primarily basketball conferences and basketball is king. The additions of Memphis and Temple by the Big East, and Pitt and Syracuse by the ACC are proof this. Additionally, the Big East added Temple and Memphis because they are in large media markets. Yet all four schools admittedly have fairly weak football programs, and none have a particularly large national following.
The Big Four (SEC, Big12, Big10, and Pac12), on the other hand, are all football conferences first and foremost. Yes, they have some strong basketball programs -- especially the SEC, but football is still king. That is why these four conferences will expand based on football strength first, and media potential second, and academics third. Money rules, and academics really have nothing much to do with bringing in the big bucks these days.
So who expands first? The obvious choice is the Big12, what with the conference only having ten schools, as well as all of the expansion rumors regarding Florida State. I believe that they will expand to the east, both north -- probably taking the strong football and basketball programs of Louisville and Cincinnati, and/or possibly VaTech (to pit against WVU); as well as south -- FSU and possibly Clemson, GaTech, and/or Miami. There is also rumors that if Notre Dame was to ever leave football independence, they may pick the Big12 over the Big10. (They originally showed in interest in the ACC, but that would be fruitless now.)
Next the SEC with reach into new market territory and grab a couple of the better ACC schools that the Big12 didn't want. The SEC is a strong basketball conference and so may even go after basketball schools such as UNC and/or NC State.
As for the Big10, of all the Big Four conferences, they care the least for football power, and likely will go after strong regional basketball schools with decent football programs such as Rutgers, Temple, maybe even UConn, Pitt and/or Syracuse. Or they may even reach south and take one or two ACC schools.
Lastly, the Pac12 will have little choice but to take the strongest football schools in the west: SDSU, BYU, Boise State,and either Hawaii or Fresno State. Who else is there? Word last year was that Texas, Oklahoma, OSU, and Texas Tech may have been headed to the Pac12, but with the Big12 expanding east, and making a ton of media money, I don't see that happening now. Of course the Pac12 could pull a complete fast one and take a school like UNLV due to is media market and basketball program, but I doubt it. In the Pac12, football is still king, and UNLV football stinks big time.
So, there you have it. Now that the four 16 school superconferences have been formed, how should they be set-up and how should they operate? The two plans most mentioned are a) Two 8 school divisions; or b) Four 4 school pods.
Personally, I like the idea of pods. Stay at twelve total games: nine in-conference and 3 non-conference. Operate like the NFL. Play every school in your pod (equivalent to NFL division) twice, plus an additional school from each of the other three pods, plus three more non-conference games. Then instead of one conference championship game between two division champs, you have two semi-finals between the four pod champs with the two winners moving on the conference championship, and that champion getting a spot in the BCS Final Four (my name for the future playoff).
This conference semi-final set-up will help to truly establish who is the best school in each conference . Under this plan, there is no way that more than one school from the same conference could ever be ranked in the top four. If UGA, Arkansas, LSU, South Carolina, and Alabama had been forced to smack each other around in a conference playoff, then only one SEC school would have finished ranked in the top 10 at the end of the 2011-2012 regular season, rather than four. This plan assures that only the four major conference champions are also the top four ranked programs in the country.
Once that is all in place you can then have your four team BCS Final Four, and the rest of Division 1A football can go off and form their own new mid-major conference with their own NCAA National Championship. The schools that are left will still have plenty of great schools with enough fans to keep them in business. Because, let's face it, in today's world of big money and big vs little in the recruiting battle, there just are not going to be anymore Boise States. And that is just the sad, but honest truth.