Sorry if this has been covered, I couldn't find it on a search.

How does the quality of HD DVD compare to HD on Cable? I know it depends on the movie etc., I'm just looking for overall.

There is a big difference on my 65" screen between standard dvd's and cable 480i digital, so I was wondering if there was a difference like that between HD disks and HD cable. Probably not would be my guess because it's hard to imagine the quality improving that much.

There is a difference. The format imposed on broadcaster is MPEG2 and capped at 19Mb/s (including audio). By comparison, Blue-ray disks are running at about 24Mb/s (max 48Mb/s) MPEG2 (or 16-24Mb/s MPEG4) while almost all HD-DVDs are at max 16-24Mb/s MPEG4 (all with audio).

Two things will (might) happen in the future:
1) BR and HD disks will get better and better as they get closer to their maximum (depends on how much "special features" are added to disks or if players will move to a "4+layers").
2) There is pressure to force all cable and TV devices to include VC-1 (MPEG4) codec to benefit from improved compression while maintaining the 19Mb/s cap.

Note: Some of the numbers above are from memory and also depends a lot on movie studios.

Cool, thanks. So generally it's an obvious improvement or subtle? To me the jump from 480i digital cable to dvd quality is obvious/substantial to give you a point of reference.

The difference is currently not as big (far from it). It will become eventually when enough HD-TVs can use 36-bits color, 24 frame-reates for movies and so on. But for now, (I have HD-DVD) the difference is there, but not enough to say "yuck!" on cable HD!

I don't know if this is still accurate, but when I had HD on cable, scenes with a lot of motion always became a huge jaggied mess. I'd say that's the biggest difference.

That is usually caused by an insufficient processor in the decoder. How long ago was it? Do you remember the decoder's brand name?

I have no idea. It's been probably a year? My sense of time is horrible.

I got HD cable about 18 months ago, and the box they gave me was already 2 years old, with some sort of HMDI version that only ever worked with itself. It was just horrible.

When I complained (actually cancelled the deal and demanded to be re-imbursed), they finally "found out" that they had a newer model in stock. That one works a lot better (HDMI is still not really working because of insufficient output speed), but is still far from good. (I have heard that my cable company--Videotron--is at last getting rid of those awful Scientific Atlantic boxes).

In general, large cable or phone companies operations' departments do not like to deploy new machines unless they are forced to (because of retraining and stuff). So you possibly had a box that used to be top-of-line when they started to evaluate and deploy it quite some time ago!

I don't know that there is as big of a jump as SD to HD on Cable. I have both Bluray and HDDVD. It's nice, but as compared to DiscoveryHD, it's not a "WOW" difference.

I couldn't even tell the difference between 60fps and 24fps to be honest with you.