Well, not "rumors," per se, but rather the head of FSU's Board of Trustees saying the Florida St. Seminoles should listen to what the Big 12 may or may not have to offer. Not exactly rumory anymore. Oh, and coach Jimbo Fisher going along with whatever he was asked about the Big 12.
Either way, here's Florida State president Eric Barron on the matter:
Florida State University regrets that misinformation about the provisions of the ACC contract has unnecessarily renewed the controversy and speculation about University's athletic conference alignment. Florida State respects the views of the Chair of its Board of Trustees that, of course, any university would examine options that would impact university academics, athletics or finances. At the same time, Florida State is not seeking an alternative to the ACC nor are we considering alternatives. Our current commitments remain strong.
BOT chairman Andy Haggard's issues with the ACC, as shared by Warchant.com, were indeed incorrect on the exact matter of third-tier media rights, a central issue in the whole dispute. However, Barron isn't exactly in sole charge of this matter, and if the board were to eventually decide it's time to go, then it would be time to go.
Then again, all we've heard is a bunch of anger from FSU's side and very little actual interest from the Big 12's side. (It's hard to imagine the Big 12 wouldn't be interested.)