I have to disagree with you here, Brian. I have rented HD movies from Comcast OnDemand and the picture was great on my JVC RS1 projector and 104" screen.
And DiscoveryHD is spectacular. Cable and dish certainly
have the
potential to supply bit-rates which you can't
tell from BluRay. Unfortunately, we may be at the zenith of
decent quality broadcast HD.
As cable and dish networks try to cram 100+ channels of
pseudo-HD into their limited bandwidth, the bit-rates drop
and quality suffers. From day one, I saw a big difference
in the local OTA broadcasts. CBS is much better than Fox
where you and I live. Both look better than SD, but I'm
very thankful The Masters is on CBS.
Being a pessimist, I expect dish and cable will pursue the
Chock-Full-O-Channels route and leave the high-quality
HD content to BluRay hardcopies. Then the difference
between BluRay and cable/dish will be more apparent.
Technology is moving rapidly enough that broadband really could steal the show from BluRay in a very short time.
High-quality HD is indeed streamed on the web in Japan.
But most houses there have access to 10 Gbps fiber optic
networks. So the technology exists now, but America
doesn't have the money to install the infrastucture. After
all, the US is a bit larger than Japan. The project size alone
means it will be another decade before anyone outside big
cities will benefit from ultra-fast networking adequate for
streaming HD content.
Just look at what music downloads are doing to C.D. sales.
It may seem contradictory at first, but I suspect consumers,
especially young folk with perfect vision, are much more
discriminating of their video quality than their audio.
We all half-listen to compressed audio while performing
other tasks like driving or jogging, but that doesn't work
with video. There is no HD equivalent to iPod "ear buds".
The closest consumer product is the back-seat LCDs in
mini-vans which pacify our kids on long trips.