.they just don't want the same thing as us.
True, and there are things about Japanese culture which make their cel phone market very different from ours. One of the biggest things is the way in which the Japanese commute to and from work: Japan has a much higher use of public transportation than does the U.S., and the Japanese are heavy users of rail travel. This means, according to the last figures I checked, the average Japanese working person has an hour commute to and from work which is, essentially, free time. Contrast this to the U.S., in which the majority of people drive to work.
To me, this explains a lot of the Japanese demand for the use of video and TV on the cel phones, and from the cel phone networks: they have the time and inclination to use those services. Contrast this to the U.S., in which people have to (supposedly) concentrate on their driving; we have lots of talk radio here, something to listen to during that commute which requires no hands.
Add to this all of the other commuting the Japanese do via rail and you have a market which just doesn't exist in the U.S. I think this holds true in Europe as well, which also has a higher incidence of public transportation use than the U.S. We drive here, a lot, and that niche just doesn't exist. Most Americans get their online TV and video either at work or at home. Which is to say that population and work patterns influence technology adoption and use as much as, or more than, GUI design and technical achievement.
At least that's my theory.