Cable Boxes and Firewire?

Yesterday, I was reading Anand's article on the feasability of a Mac Mini HTPC and he did something pretty cool. Apparently, cable companies are required to give you a cable box (digital cable?) with a firewire port if you request it. So Anand hooked the Mini up to it and was able to basically function like a DVR. It pulled a MPEG2 stream off the cable box. This was news to me (I'm stuck in satilite hell).

I was wondering if you can record more than one show at a time using this method? And it's obviously not limited to Macs, so are there any Windows/Linux projects that take advantage of this feature? Hell, the program he was using was able to completely controll the cable box straight from OS X.

It sounds like its probably a standardized interface. That's pretty cool.

Yeah. It looks like a pretty good replacement for normal DVRs, but I don't see the point if you can only record a single show at once. Its not like I leave my house often.