Apple has released iOS 6.1.3 to end users today. It is currently available over-the-air via Software Update in the Settings app.
The update includes a security flaw fix involving the iOS device Lock screen. Additionally, the new update includes fixes for the Apple Maps application for Japan.
Apple previously released these Japanese Maps fixes over-the-air to non-iOS 6.1.3-beta devices, but it appears that the actual update might include even more improvements.