I have a new bit of speculation, though I'm not totally going to take it to the bank just yet. Could there be any chance that the four teams with promos -- Tammy & Victor, Mel & Mike, Margie & Luke, and Cara & Jaime -- were given promos because they're going to be the actual F4, and CBS was trying to hint at that?
If so, I'd find that to be an awesome F4! A women's team, a brother/sister team, and not one, but two parent/child teams being the last four teams standing? I think TAR14 will be made of win if something like that happens!