The site references a tweet from @sanzomon which reads:
It may be known information, the data in the standard Map iOS has been updated dramatically sudden. Position information has become quite accurate.
Apple has released several betas to developers that highlight improvements to Maps for the country. Those improvements included:
● Improved pronunciation of roads during turn-by-turn navigation
● Optimized directions to more strongly prefer highways over narrower roads
● Now indicates upcoming toll roads during turn-by-turn navigation
● Added labels for junctions, interchanges, on-ramps, off-ramps, and intersections
● Added indicators for transit station buildings, subway lines, and traffic lights
● Updated freeway color to green
● Updated icons for some location categories including fire stations, hospitals, and post offices
● Added 3D buildings including Tokyo Station, Japan Imperial Palace, and Tokyo Tower
It was expected that these improvements would come alongside a new firmware release; however, it appears Apple may have pushed these out already.
Read More [via Simon]