I will make a note that I am in the Blu-ray camp, but have been nearly tempted to add the HD-DVD add on for my xbox 360. Anyways, there are benefits and drawbacks to each format. There are a few format neutral film companies (warner bros and new line mainly) that produce movies on both formats. Blu-ray has Sony, Fox, and Disney exclusivity, so movies like the James Bond, all Disney/Pixar movies, etc are all Blu Ray exclusive and will not be converted to HD-DVD. There is a new standard for HD-DVD for triple layer DVD's which may make current players obsolete if they update their technology. That's just a rumor I'll add. HD-DVD has Dreamworks, Paramount, and Universal exclusivity so TV shows like Heroes, the Shrek/Bourne series, and Transformers are only on HD-DVD.
In terms of sales, Blu-Ray sales are 3 to 1 in the US, 7 to 1 outside the US. Hardware sales are 3 to 1 blu ray to HD DVD if you count PS3 sales. HD-DVD has the edge in terms of pricing for their players.
From what it appears, if Warner Bros goes Blu-Ray exlcusive next year, since 2008 is rumored that they will finally make a decision, it means that a good 70% of all the total movies produced on either format will be Blu-ray or blu-ray exclusive.
Given that apart from fanboys and early adopters, most standard familes looking to eventually upgrade will probably not want to do so without the ability to play lots of Kids movies (strike 1 for HD-DVD), Toshiba had to pay Paramount and Dreamworks 150 million dollars to choose their format when each was format neutral at the beginning of the year (showing that Toshiba clearly needed to try and even things out in the format war), and that neither side is willing to budge, my guess is that blu-ray will win out in the end. However, if Warner goes to HD-DVD, well then it's back to square one and no matter which format you choose, you may end up with a 3-400 dollar paperweight.
Hopefully this helps.
By the way, if you're looking for lots of information about the format war and its developments, check out digitalbits.com