Are the Packers the only good team in the NFL that the Patriots haven't beaten? There's 6 playoff teams per conference. The Patriots are, of course, one of those.
Of the other 11 -- the Jaguars, Titans, Colts, Steelers, Chargers in the AFC, the Cowboys, Giants, Redskins, Packers Bucs and Seahawks in the NFC -- the Patriots have, remarkably, had to play all but Tennessee, Green Bay, Tampa Bay, and Seattle. (And, let's face it, Tennessee and Tampa Bay really weren't very good.) They also had to play the Eagles, who were pretty good but unlucky enough to play in the best NFC division, and the Browns, who were probably better than the Titans anyway but had a tough division schedule, too. (I guess the TOUGHEST schedule would have been if a team in the AFC South or maybe North had to play out-of-conference against the NFC East. But, really, the Bills weren't a bad team. The Jets and Dolphins I have no excuses for.)
Is there any reason to think that they can be stopped? Well, yes: the refs certainly tried to give the SD-Indy game to the Colts. That game was nearly a travesty, and the officials need to be investigated for whether they have consorted with gamblers and if they, themselves, had money on the game. Just because the right team won doesn't mean that the discussion should end.