It will not be 12, Texas and OU are against it. They calls the shots. WVU or Lville will be the 10th team and that's it. Small chance to go to 11 but I don't really see a reason.
Big 12 has missed out on the national championship game something like 3 times out of the past 5 years because of the conference playoff game. Less than 12 teams makes the path to the national championship game much easier with the BCS system currently in place. B12 does not have equal revenue sharing so having additional teams and playoff game does not benefit the big teams (Texas/OU) like it benefits all teams in a conference where the money is split evenly.