Not necessarily all true HD, but:
I watched a little of that "watch instantly" feature that netflix has today, and it was DVD quality - actually, a little more than that through my HTPC upscaling
If you have the HDD space on your DVR, you can record a movie off any of the HD channels and keep it indefinitely
Upscaled DVDs look pretty damned good through the PS3
Point is, a lot of people are going to consider that "good enough" for most movies, and there weren't such options available in the early days of DVD. It was either DVD, VHS, or Laserdisc lol. HD has a lot up against it whereas DVD didn't.