Since very few "broadcasters", cable, satellite, and OTA send a 1080i signal giving preference to 720, it depends.
If you have both, a OTA antenna and cable, use which looks best to you.
If you're going to get an HDTV, you should know you can get HD broadcasts over the air (OTA) as well as through cable and dish. I just bought an HD antenna from Antennas Direct in anticipation of my LG 30FZ4D HDTV. My cable box also supplies HD but I want to have the choice. My understanding is that OTA provides an even better picture since the signal is not compressed as it is for cable and satellite. Does anyone have any information as to the validity of that statement; I'd appreciate your thoughts.

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