(A full review of Apple Maps Japan Transit here)
Apple Maps Japan Transit service has gone live before the official iOS 10.1 release and Apple Pay Japan launch. iOS 10.1 beta users and macOS Sierra 10.12.1 beta users, can now search transit routes nationwide, even reaching tsunami recovery areas such as Yamadamachi in Iwate (screenshot below), with multiple transit time, fare and transfer results.
Apple Maps Japan cartography has been updated to show color coded train and subway lines, bus stops, completely new transit signage, enhanced station footprints and indoor mapping. Japanese Siri also supports transit route searches.
Rough spots remain and it appears as if this is a final beta test before the official Apple Pay Japan/Japan Transit rollout with iOS 10.1 update on October 25 (local Japan time). Indoor mapping for example, shows overall underground station connecting structures in pink, but multilevel underground detail, passageways and exit information is missing.
There is much to review and test in the next few days with more updates to follow. Until then, I posted some quick screenshots below. The images more or less resemble earlier Apple previews though there are some differences.