But this is a topic that really interests me. I am of the belief that there will be continued expansion and that there will be 4-5 conferences of 16-18 teams in the near future. As for the Big Ten, although there are a lot of options that exist. If I were to guess just for the fun of it as to who the 4 would be should the Big Ten go to 16 teams, these would be it:
Texas - They've already been told (or so that's what I've heard) that they could keep their Longhorn Network or whatever it's called if they joined the Big Ten. We also know that Texas was wanted by the Big Ten. Eventually, they'll move because the Big 12 is going to continue to get ransacked. There is one problem with them moving, and that is,
Texas Tech - The Texas State Legislature is not going to let Texas join another conference without their little brother coming along, therefore, I think they would be part of the expansion.
Notre Dame - I think they'll eventually have to join a conference, for a lot of reasons which have been listed on this thread. But, there's another reason that may develop as well. I don't know if this will ever be the case, but with superconferences, it might come to the point of a playoff and only conference winners would get in. This one's a longshot, but it could happen. We already know there's more money for ND to join the Big Ten with the BTN and profit sharing, so they may run out of excuses at some point.
Missouri/Rutgers - It could be Missouri, but by the looks of things, Missouri may get offered the SEC at some point. If not them, than I could see Rutgers, or actually even Pitt.
One of the more interesting things is trying to figure out where all of the pieces will fall. If Clemson, Missouri, Texas A&M and FSU all really did join the SEC, than the Big 10 and the Pac 12 would be forced to expand. Also, the Big East and the rest of the ACC would likely merge, leaving some remnants. The Big 12 wouldn't really exist anymore. Teams that could be struggling to find a conference could be: Kansas State, Louisville, Cincinatti, Iowa State. Who knows, but it could get really interesting.