Japanese Sakai schools meet three times a year, at JA Sakai,  at Open Apereo, and a JA Sakai unconference.
This year, JA Sakai had 60 participants representing 7 universities. It was held at Tokyo Metropolitan University (TMU), which is the largest public university in Japan, and an influential institution. TMU presented first on their first year using Sakai. TMU has created 7700 sites but only about 20-30% of them are active. From what I can tell, generally they seem happy with the first year, and it sounds like a big part of their success is their partnership with Apereo commercial affiliate KEL.  NS Solutions is the other Apereo commercial affiliate in Japan, also well respected and an important part of the Japanese Sakai community. Japanese schools have an interest in learning more about other Apereo projects, expanding and developing LTI connections, and exploring Learning Analytics.
Many of the JA Sakai schools are on Sakai 2.7 and considering how to update to Sakai 11, while taking into account the full range of change management issues (training, help documentation, integrations, etc.).  Kyoto University is on Sakai 10 and has realized the value of keeping up to date with community releases for easier integration of patches and incorporation of security fixes. 
The Japanese Sakai community represents an interesting model of close collaboration between Saka institutions and Apereo commercial affiliates to reach out to higher ed institutions and show the value of Sakai in the LMS marketplace.