That’s a great question, and some people may have different answers, but for me:
+ More and better movies - both already released, and in studio vaults;
+ The best upscaling of standard definition DVDs, so you can get even more enjoyment from the movies you already own;
+ Less expensive players - the cheapest Blu player is 4X the cost of the Toshiba at WalMart;
+ HD DVD players are complete - all HD DVD players come fully enabled to play all the movies and special features, including online content as all players are network and web enabled;
+ HVD is much more pro-consumer - no region coding, no Sony spyware as placed on all PS3s, etc.
There are more reasons, but these are the ones that come immediately into mind.
Blu-Ray to date has more titles, and the "quality" of these titles is a matter of opinion. This is arguable however because a dozen or so of the Blu-Ray titles have been discontinued, and some of them were REALLY bad MPEG transfers. Case in point The Fifth Element; it was so bad that Sony had a free mail in program where you could mail it back for a replacement transfer that was created because of the controversy over its quality. My friends Remastered Platinum edition DVD actually looked better than the 1st generation Blu-Ray.
Secondly, region encoding isn't something that I would call anti-consumer. Its a basic measure to cut down on foreign bootlegs, and was something that most DVDs have had throughout the years. I've never ran into an issue with it, although I'm not into buying Japanese manga bootlegs or stuff like that. Most consumers will never have a problem with it.
I would also add that the rental store market (at least in my neighborhood) is almost exclusively Blu-Ray. For example, the HD-DVD version of Hot Fuzz (it was a Universal title, so it didn't come out on Blu-Ray) was heavily backordered on Netflix. But I was anxious to see it, so I decided to try and go rent it. I went to 6, count 'em 6, movie rental places in my neighborhood, and not one of them had a copy, or even one on order. I didn't even see any HD-DVDs to rent. Everything was Blu-Ray. This of course could change with the strategic partnerships between the studios and rental corporations constantly changing, but that is the current situation.
Both formats are going to be around for a long time until one format gains a monopoly on the studios, or the studios decide to offer both formats on everything.
There is a lot of excitement about this on other forums. Looks like my dad is going to be joining in on HDM for Christmas with a new HD-DVD player! If not the A2, then maybe an A3.