Just left a php conference here in town. 2 million people, do had decent turn out of about 130 people.
Of course, I didn’t chat everybody up but did get a chance to chat with a few presenters, one who is pretty influential and talked about the history of php.
Symfony and cake + Postgres and WP are key players over here in SonyLand. Besides crappy spaghetti code 
Yeah, I’ve seen some crazy present day code. I’m a crappy programmer but they still take the cake!
Anyway, it comes down to something simple!
Documentation and books!
Japanese are very tentative about their English skills and are also very follow the leader.If 1 or 2 majors got on board you’d see a huge adoption rate.
I chatted a bit with the the organizers! (only whitey - so I tend to be a magnet at times) and they asked if I’d be willing to do something the upcoming open source conference. Not php centric but they are interested in having fresh input for the English speaking world.
If Yii is interested in being presented there let me know!
Cheers