Just got HD cable today. First, let me say it is AMAZING! I can't take my eyes off of the Discovery Channel, nor the Monday Night football game tonight! My question is why are some of the HD channels in 4X3 instead of 1:78? I thought all of HD was in "widescreen." Also, some seem to be in 1080i (Discovery, Football game, some HBO, etc.) while some look to be 480P? Tombstone (Kurt Russell) was on earlier, but it didn't look 1080i --- more like 480. While Terminator 3 was on another station and it surely was 1080i. Is this common for them to mix them up like this?