Many Japanese people who are interested in selective mutism also use social network services. They share information about selective mutism in SNS.
Popular SNS among them are mixi and Twitter. Facebook and Myspace are not so popular among Japanese people.
* mixi *
Mixi is the most popular social networking site among Japanese. Mixi is a Japanese website, so I guess most users are Japanese.
For more detail about Mixi, see http://en.wikipedia.org/wiki/Mixi
At present there are 6 communities about selective mutism on mixi. The largest community has over 260 users.
* Twitter *
Twitter is also popular among Japanese people. Yukio Hatoyama, Japanese Prime Minister, and Sadakazu Tanigaki, a party leader of Japan's largest opposition party, are also Twitter users.
Japanese people who are interested in selective mutism also use Twitter. Some of them are members of a Japanese support group for selective mutism and share information about the group activities.
* My mixi and Twitter pages *
I also use mixi and Twitter. All my posts are Japanese, not English, though. But I don't join any community on mixi. I only keep a diary on mixi to record updates of my website. I don't also communicate with people through Twitter very much. Usually I tweet to myself.
My mixi and Twitter pages are here. I'm afraid you can't access my mixi page unless you're a mixi member.
http://mixi.jp/show_friend.pl?id=8699233
http://twitter.com/nesamimus
Index of SM in Japan