HD-DVD and Blu-Ray are indeed seperate and incompatible formats. It's like VHS vs. Beta if you need a reference. Or DVD-Audio vs. SACD.
So what do we have? The vast majority of people do NOT own a high definition television. Sure, the market is growing, but the VAST majority of people still have a standard definition set. And the VAST majority of people do not have surround sound. And of the people who do have surround sound, no one (outside of a few technicians or really really rich people that I don't know about) has a receiver or pre-amp that can decode Dolby Digital TrueHD, Dolby Digital Plus or DTS-HD, which are the "high def" sound formats to go along with the high def picture. So even for the early adopters, there's going to be a waiting period until the new sound formats are supported in receivers and pre-amps. Furthermore, DD TrueHD, DD+ and DTS-HD all require more bandwidth than S/PDIF or optical offer, so the new recievers will have to have FireWire or HDMI. And for those who have receivers with HDMI already, I'm not sure if the current HDMI 1.1 spec will work. The new HDMI 1.2 spec really only adds SACD support. So we may need a 1.3 spec for DD TrueHD et al. And who knows if current 1.1 spec receivers can simply be upgraded, or if we'll need a whole new receiver!
What I'm getting at is this: in order to make use of the high definition picture and the new "high def" sound formats, the VAST majority of people would need a Blu-Ray or HD-DVD player, a new TV, 7 speakers and a subwoofer and a new receiver. That's a HELL of a lot more than what's needed to see that DVD is superior to VHS. Even on a standard def 27" TV using the speakers built into the TV, DVD is clearly superior to VHS in picture and sound quality. THAT'S why DVD has been such a huge success.
HD-DVD or Blu-Ray is a whole other ball game. A tremendous amount of equipment (and therefore money) is needed to really see or hear a difference from DVD.
And all of that is without even considering the confusion of having two seperate, incompatible competing formats!
I'm sorry to say, but I think MOST people (not us home theater nuts) are just going to say "why would I buy either of those? I've got a DVD player and it's fine!"
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