If OU and Texas start having crossover games with a Bama, Georgia, etc., on top of their conference games, whoever they may be -- I'm guessing teams like A&M, LSU, etc. -- the last thing they are going to do is schedule more high profile OOC games.
Same can be said with USC, if they end up playing OSU, UM, PSU, etc. in conference -- they aren't going to be scheduling ND as the last thing they'd want is another cross country trip. I'm sure if ND agreed to travelling to USC for the game each year -- they'd be alright with keeping it going.
I think these superconferences are going to put an end to alot of long standing rivalry games. The end goal for teams is still getting to the CFP, but they aren't going play a murderers row of teams each year to get there.