The real cultural hurdle isn't the indirectness in Japan, it's the burdening sense of obligation Japanese people who are connected socially feel to one another. Facebook already feels like a part time job to me, but transplant an urban Japanese's persons relationships as well as their loose ties onto a social networking site...that would be a lot of work for them to maintain that sense of equilibrium in all those relationships.

But if they do try, they should totally get Joi Ito's help.