They're talking about Belichick talking to his son in private, as they walked off the field together after the prime time game vs the Jets.
He said something about the NYJ being the supposed #1 defense in the NFL (Belichick's thoughts, not stats), and how we just lit them up. He also threw in a 'suck my #%$^' for good measure.
The bottom line was that it was a private conversation though, and if there hadn't been a camera/mic or reporter around, (I forget who claimed they heard it) he never would've said anything about the Jets.
I am sure that the majority of the teams and coaches say things all the time in private. Other than that, I've never really heard him say much bad about the Jets, or anyone for that matter.