We've been mostly speaking of blu-ray and HDDVD in two different ways. First has been in the console wars (since as gamers, that is on most of our minds), then there has been the players for our TV's. There is the third as it applies to PC usage.
Which market will be the one to ultimately tip the scales one way or another? Of course they are all interrelated, but there will be one that drives the new tech the most.
I don't think it will be the players for TV's. Many video stores are already going the way of the dodo due to the ability to simply order movies on your satellite or cable TV. They try to blame it on piracy, but I'm not so sure about that. Here's a consumer thought: "I just spent a grand on a wicked TV, and you want me to drop how much on a stupid player? I already have HD ESPN, what do I care?"
The one to push it will probably be PC's. If you can get some programs that absolutel need the storage space of a blu-ray or HD, then it will be bought. That's why I bought a DVD burner in the first place. My CD burner just wasn't able to handle all the info I wanted to store.