Got the R2 DVD this morning. The HOBL is all in color, but there's a lot of restored bits in it as well, mostly gore. Here's what I've noticed so far:
-"Revenge is a dish best served cold. (-Old Klingon proverb)" card before credits has been replaced by "This film is dedicated to master filmmaker Kinji Fukasaku, 1930-2003"
- Origin of O-Ren anime has several inserts of Matsumora's death; katana slicing up torso, exposed intestines, about 4 inserts.
- Go-Go's Intro has an extended shot of the disembowelment of her "friend", showing intestines hitting the floor.
- House of Blue Leaves is obviously in color, but also includes several additional shots, more than I could keep track of. Of note, a reaction shot by Sophie to a dismemberment of a Crazy 88, and several additional gore shots, as far as I can tell so far.
- Sophie's interrogation has the addition of The Bride hacking off her right arm, blood hits camera.
This qualifies the Japanese version as an entirely unique version of the movie.
There's also a ton of additional supplements that aren't on the US DVD, including a lot more making-of material on the anime sequence, and a behind the scenes video, unnarrated about the HOBL.