blue ray is pulling away from hd dvd. its delivers a better picture, it upconverts with minimal flaws, not to mention it has contracted with a majority of the major movie production companies.
My opinion only, but I'd say its a draw for the most part.
Picture Quality: draw - both tend to use highly quality codecs at good bitrates
Sound Quality: draw - Dolby TrueHD (HD-DVD) versus Lossless PCM (Blu-ray)
Number of Signed Studios: Blu-ray advantage
Pricing: HD-DVD advantage
Currently Available Selection of Titles: really poor for both -- draw (really depends on which specific titles you like and want)
Gaming: Blu-ray advantage (PS3)
Interactive Features (e.g., picture in picture commentary, web interactivity, etc.): HD-DVD advantage
Upconversion Quality of Standard DVDs: draw (perhaps a slight advantage for HD-DVD players as a whole)