television

Aaron62

Read this: YouTube Tests Higher Resolution Videos

and this: High-quality YouTube videos coming soon | Webware - CNET

but I'm not sure exactly how to answer your question. Most videos are compressed to 320x240, so a traditional TV that displays 480i @ 4:3 is much different.

1inxs

If you have a 5 Mbps broadband connection you can select HD quality and if the selected video is streamed in 1080i HD and your video card supports HD, and your connected to an HTDV, your TV will show 1080i HD quality. It's not downconverted from your PC to the TV. What ever your PC sends out is what the TV receives. If any of these are not supported, you will only see 480P.

television

Makes sense I think, so if I expand the video on the PC, this will cause a distortion? 1inxs, your 480p answer seems to contradict Aaron's 320x240 answer right? Sorry, just want to make sure I understand correctly.

1inxs

Maybe this will help you get the answer you want.
Hulu - Support
Some of our videos now come in a 1,000 Kbps, H.264, 480p stream. You can recognize these streams by the 480p Hi-Res button that will appear in the lower right of the player. To watch these high-resolution streams, you'll need to upgrade to Flash Player 9.0.124.0. We recommend a downstream bandwidth of 1,500Kbps for the smoothest playback experience.