Super, I found many groups and discussion communities for Science Communication on different SNS site. Among those, I found [facebook] is most credible for information quality and group building, next to this, [orkut] from Brazil is not bad, and [vkontakte] from Russia is also my findings. Of course, on japanese SNS [mixi] MIXI.jp, there exists already such communities.
I created a group "Science Communication Japan" on [facebook].
* Ref) SNS in the world.
[yahoo 360] http://360.yahoo.com/