updated 01:39 pm EDT, Mon March 11, 2013
6.1.3 update still in beta
At least some promised Maps upgrades are reaching Japanese iOS users even though iOS 6.1.3 isn't available to the public, says Japanese site Macotakara. The improvements were originally slated to debut in v6.1.1, but were postponed when Apple had to deal with several major glitches. It's not clear how the v6.1.3 changes are propagating without new firmware, but at least some changes might be possible via updated map downloads.
It's also not clear which improvements are now in effect. In beta notes Apple has promised things such as new and/or revised labels and icons, and extra 3D-rendered objects, such as the Imperial Palace and Tokyo Tower. More difficult to implement without an iOS update may be several turn-by-turn navigation tweaks, such as better pronunciations and optimized directions.