According to Kansas City sports radio, the Big Ten has extended membership offers (actually, it's likely offers to apply for membership) to Nebraska, Missouri, Notre Dame, and Rutgers.
If Notre Dame remains independent, Rutgers would be the 14th team. The Big Ten would then decide whether to stop at 14 or extend offers to two other schools (maybe Pitt and Syracuse?). If Notre Dame joins, sources say an offer will be extended to one other school making it a 16-team league.
As a former resident of Kansas City, I agree with what Jon Miller wrote about the connections of this station and its management. There could well be legs to this.