Some of you may remember meposting about my Panasonic HDTV 42 plasma(TH-42PX20). You may also remember that I was upset to read in the manual AFTER buying it that is only accepts 480p, 480i and 1080i NOT 720p.
I was doing some research on the panasonic site and found the following information.
True High-Definition Images (TH-42PX20/TH-50PX20)
Panasonic Plasma Displays set the standard for high-definition viewing. HD panels with approximately 1,050,000 (1366 x 768) pixels and 790,000 (1024 x 768) pixels capture all the beauty of HDTV broadcasts and other HD image sources. They support all major HDTV and EDTV standards, including 1080i, 720p

and 480p, and fully reproduce high-definition pictures from 720p HDTV signals.
Its says right there 720p!!! but I have done a test with my XBOX and it doesnt work. What woul dyou do if you were me?