The TiVo HD should be able to do what the Direct TV boxes do... Let's say for instance that NBC is channel 5. With Comcast Memphis, digital NBC is 205 and NBC HD is 805. All of these three channels have the same programming, just in different formats. The TiVo should be able to map 805 to channel 5, so that I'm never watching the SD version of a show if the HD version is also on TV. This became very apparent to me when TiVo was recording the SD version of Ugly Betty as a suggestion while the same thing was on the HD channel. I have a friend with Direct TV, and he said he just goes to channel 5. If HD is available for that channel, he sees that instead of SD.