If your cable provider is anything like the one Down Unda (Foxtel), then most channels are going to be over-compressed with visible artifacts. This is the main reason I won't buy it.
(It seems to be most prevalent on the music video channels, and that looks like it might be starting to teach producers that such artifacts are acceptable: Pink's latest DVD has been on show at a local department store for a few weeks. It is obviously over-compressed and a poor demonstration of their TVs. They should go back to Pixar movies. But it's more worrying that the DVD's producer thought this was acceptable for a DVD release.)
And HDMI/DVI carries uncompressed digital video, not compressed.
Wade.