There have been four iterations of the iOS 6.1 firmware so far, with the latest being released on December 17th. iOS 6.1 was originally slated to be released sometime in December, but it was then pushed back to January. As for what day in January this is yet to be seen, but rest assured it will indeed be released sometime in January.
According to the German blog iFun, iOS 6.1 GM could actually be released as early as tomorrow. For those of you who don’t know the GM version of an iOS firmware is the same version that is released publicly. Apparently Apple is testing the GM firmware internally, but is ready to push it to developers on Monday.
The iOS 6.1 firmware doesn’t bring about a phenomenal amount of new additions, besides the ability to purchase movie tickets with Siri, better iCloud security and a new iOS 6 Maps framework for developers.
It is worth noting that we could actually see the release of the iOS 6.1 Untethered Jailbreak for all devices shortly after its release. As Planetbeing recently stated in a Reddit thread that he was waiting for its release before he pursued getting anything ready for public distribution.