The XBox HD DVD drives are flying off the shelves. Obviously, watching your fave movies is what you really care about. But if you're looking for a disc that shows off the HD DVD format's interactive capabilities, Tokyo Drift is the best example out there. It's that or Miami Vice. Seriously.
While we can't vouch for the film itself, we can verify the disc's extras are amazing, including full storyboarding, technical specs on all the cars, GPS mapping of all the chase scenes, and the ability to watch some parts of the movie with repainted cars:
A car's tech specs will flash on screen occasionally.
And the picture-in-picture is actually a separate datastream, which goes to show off HD DVD's extra video decoder (it's part of the spec, and no Blu-ray drives currently ship with a second decoder.)
The producers have set up a little animation that can be turned on during car chases, highlighting the path the cars are taking through Tokyo. (Fictionally, since a great deal of the chases were done in LA.)
Is the movie shit? I don't know. I kind of like it. But the movie's extras go a long way to showing off HD DVD's capabilities.