AFAIK, Comcast Basic service, and probably the other cable companies, 
provide just the public cable access and local government channels as 
part of the "free" service. It DOES NOT provide the cable version of 
local OTA TV channels. When they talk about receiving local TV channels, 
they mean the Over-The-Air channels are received with your regular 
roof-top antenna or rabbit ears. I'm not even sure if you get a cable 
box with "Basic" service or have to use your cable-ready TV tuner.

The requirements for minimum basic (or universal) service are part of 
the public utilities charter under which the cable company operates. 
Since the local government (cities) want to get their word out, and the 
cable companies are forced to operate the public cable access system, 
those are the freebies you get. Everything else is a money-making service.

I don't think any of that has changed since HDTV came in. I reverted to 
"basic" service when I shut off cable TV service many years ago. I 
originally did it to keep the wire active and to save $5 a month on 
Internet charges. I think they have plugged that loophole since. It has 
probably been over 8 years since I hooked anything up to the cable....

Doug.