Does anyone know how the newest generation of Mits RPTVs handle 720p signals. Does it downconvert them to 480p or up to 1080i? I've read that Mits and XBOX 720p signals didn't work together earlier models, but I'm not sure about the newer ones. Is there any trouble watching ABC's 720p feed? I've got a 48-511 on the way and I'd just like to know what to expect.