Just a quick question on which network channels broadcast in 720p and which ones do in 1080i. Reason being I bought a HDTV tuner, hooked it up and turned to ABC (Dr. Dolittle). Compared screens vs. regular TV and wasn't blown away like I thought I was going to be. Then I think I read that ABC broadcasts in 720p and my Rear Projection doesn't do 720p, so maybe it's a poor upconversion. So if anyone would be so kind as to list the network channels and their HD formats, I'd appreciate it.