Oh! and I have an answer!
Its actually not immediately clear on Comcast or online; The info is out there but you kindof have to assemble the information yourself (unless you own TiVo, you may already know the answer.)
Comcast IS still required by federal law to allow non-Comcast gear to access their broadcast channels.
Comcast DOES still use QAM, but they've gone to full encryption of every channel they serve except locals (which by law, they must also not encrypt if they carry them.)
So if your HDTV doesn't have a "CableCard" slot, you're not getting any channels except rabbit ear channels.
In Comcast's case, they will not do any on-demand streaming, or PPV thru customers using their own Cable Card. (since those are services of Comcast and not actual broadcasts, they aren't covered by the law mentioned).
The lesson here is: if you use cable instead of others because you have or need lots of TVs in the house, buy HDTVs that have cablecards to avoid having to lease boxes from Comcast.
