It sounded pretty cool that this verson of XP Media Center Edition would be released to OEM for install, so I decided to give it a whirl. I have always loved playing with MCE systems, but never felt like paying for a whole new pc to use it.
I have a computer thats sorta my HTPC. The the graphics card is pretty ancient: an ATI Rage Fury Pro. It's a Rage Pro 128 card with 32mb ram. I don't play crazy 3D games on it, so it isn't bothersome, and has composite in and composite out. Video playback and most visualizations work fine on it. I also have an ancient TV tuner, a Hauppage WinTV. It does stereo cable tv tuning and works fine.
Of course, Windows XP Media Center Edition will NOT play video with my video card, and it will NOT use my tv tuner. My theory on why it does not support my video card is that it does not support that crazy resolution you said it outputted to work with HDTV's more. As for the TV tuner, every TV tuner that's supported with MCE does on-board MPEG-2 encoding. I guess it would make sense that you would not be able to do time-shifting, but any pc would be able to show the TV feed fullscreen, and even capture.
All in all, if it worked it would have ruled.
...but since it doesnt (
i am glad i didnt pay for it 
)