We are working on Odoo's translation together with Pro-SPIRE Co., Ltd., a newly appointed Odoo partner.
In Odoo V9 the accounting features were refactored and the menu structure changed substantially, so a lot of the V8 translation did not carry over to V9, and the translation stayed inadequate in some conspicuous places. If Japanese users are to use Odoo, we cannot leave it that way, so we are allocating a few hours of our own resource each week to the work. Over the past few weeks we have translated nearly all of the visible stock-related strings. We intend to work through the other areas in turn.
Setting Japan's local situation aside, globally Odoo can now be called the de facto standard open source ERP. It has always seemed a waste to us that software like that does not catch on in Japan — but carrying essentially all of the work ourselves is hard, and part of what we were doing was waiting for new people to join the translation effort. Now that more people are taking part, we are conscious of owing a proportionate contribution ourselves, and we are picking up the pace.
New participants are very welcome. What is good about open source is that you can act on the product yourself to improve it. Whether you provide services on Odoo or use it as a user, please do take part!
Related post: Why not join the Odoo Japanese translation team? - using Transifex
We are working on Odoo V9's Japanese translation