Well, the way I see it, the unit is CAPABLE of getting signal on any channel that is being broadcast. In other words, I don't subscribe to any of the sports packages. So on channels 700-801, I have like 70 channels that all say "You must cal 304-xxxx to subscribe to this service." While my TV and VCR DO both auto-recognise channels I recieve, it would grab those since it's actively seeing a channel and not just static. At least the Tivo removes the channels you don't recieve from the guide. My digital cable box didn't. God was that irritating.
Oh, and yes, it definitely keeps the list over a power outage. Too bad the select-play-select-3-0-select doesn't stay. I LOVE that feature, and so does the wife. Too bad she can never seem to remember the sequence whenever the power fails.