It looks like Japan won't be a part of BlackBerry's BB10 launch plans now or anytime in the foreseeable future. According to a report from Nikkei, BlackBerry has decided to stop selling phones in the country, at least in part because it wasn't able to justify the cost of making the necessary language modifications to its new operating system. As Nikkei also notes, however, BlackBerry has seen a particularly steep drop in market share in Japan, where it now stands at just 0.3 percent. We've reached out to BlackBerry about the news and are awaiting comment.
Update: We've received a statement from BlackBerry confirming that it has no plans to launch to launch BB10 devices in Japan at this time, although it adds that it will continue to support its customers in the country. The complete statement is as follows:
We are in the process of launching BlackBerry 10 globally in key markets and we are seeing positive demand for the BlackBerry Z10 in countries where it has already launched. Japan is not a major market for BlackBerry and we have no plans to launch BlackBerry 10 devices there at this time. However, we will continue to support BlackBerry customers in Japan.