FYI, Crutchfield has a pretty decent page explaining the terminology of HDTV. I've been surfing various manufacturer pages, and I haven't been able to find a clear explanation of whether you'd be screwed or not if you didn't have support for 720p input in your TV. If you can wait a day on this, some more people will chime in here with advice. Or, I suppose you could always go wade through chat boards like Audio Asylum or AVS Forum.