You_Too said: From what I've seen in screenshot comparisons here and there, the Japanese BD is the same as the HD DVD, but also has cleaner upper and lower edges of the picture. The HD DVD is bright and blurry at those edges.

I looked at the screenshot comparisons a few years ago and seem to remember that the Japanese BD is slightly stretched vertically (like some of the others). I have the Japanese discs and the theatrical HD DVD, and the difference between the Japanese discs and all the other non-Skynet releases is minor. It's down to individual impressions of small differences in grain and of the degree of edge enhancement and the like, and I'll take the HD DVD. In my opinion, the Japanese discs aren't significantly better than the other non-Skynet releases (as some have made them out to be) and weren't worth the price I paid to import them.