Facebook is not popular in Japan. It's only the IT people & the Goth people to use Facebook in my friend. But, most of my friends are said "I can't understand Facebook well".
UI of Facebook is different from Japanese SNS greatly. And many Japanese read a Web site with a mobile. The service that doesn't prepare for a site for mobile can't live in Japan.
So, Facebook released the optimized for Japanese mobile version. Such a screen appears when we access Facebook from Japan.
It's written in this way..."Site layout does not good yet, but the basic function is available. Because you don't overlook the news feed of the friend, it's convenient. Please recognize a QR cord with a mobile and try it."
So I tried this.
But, Japanese mobile screen is very small!
I like accesses Facebook in iPhone than the Japanese mobile.
By the way, MySpace went into Japan earlier than Facebook and implemented a QR cord.