Good discussion of this on KStatefans.com although, as expected, it's all speculation at this point. If anything happens, the two most likely scenarios seem to be ND joining the ACC for football membership only, or developing an affiliation with the ACC which would include ND having three home and three away games each year with ACC teams. I could see ND wanting to do the affiliation as it would keep their deal with NBC while ESPN would have to sweeten their TV deal with the ACC for the rights to broadcast the ND games. It also allows ND to keep their traditional opponents of Michigan, MSU, USC, Stanford, Navy, and one other of Pitt, Army, Air Force, and anyone else they want to work in.
I'm not pretending here to be well-versed in the nuances of the various conference TV deals, but an annual six game affiliation with the ACC seems to solve some of ND's and the ACC's TV money problems.