The disc read speed of Blu-ray atm is a problem (especially with the PS3, which reads slower than current DVD players), and there were a few other upsides with HD-DVD, although I don't remember them (something about the video quality?).
Anyhow, I still don't care terribly much about this war, as I don't have an HDTV yet (in about a half an year I intend on buying a 1080p HDTV though) - I seem to recall someone posting something here before about a format in the works that will might make Blu-ray obsolete anyway.