I think the slow takeup of the 360 might have something to do with the culteral differances that eastern and western people take to work and gamming.
In the west we will do anything to get out of work, or get rich by doing as little as possible, but in the east there is a strong workethic that says you should always do the best you can and through hard work you will be rewarded.
Where as westerners probably like having the world evaluate their gamming efforts publicaly and have their score directly evaluated besides their friends, this might be something hard for easterners because this opens them up for chritasism from their gameplaying efforts. So if I was not playing as much Kameo has my friend was then they would probably critasise me for slacking, being lazy or just being crap.
Really this is just me guessing, but there has to be some cultural reason why the 360 is flopping in Japan. And this is the best I can comeup with. It also might suggest why Nintendo and Sony have not considered online as worth while.