The main down fall for Blu-Ray is the stance they will not let the Porn industry release any movies on the format, and HD-DVD doesn't have an issue with Porn. This is the same Sony downfall as beta-vhs, Sony did the same thing in the 70's and they lost out.
http://arstechnica.com/news.ars/post/20070112-8602.html
http://www.pcmag.com/article2/0,2704,2085645,00.asp