Winocm has revealed the successful jailbreak of the iPhone 5 on iOS 6.1.4 via a picture just posted to Twitter.
In the screenshot seen below, Cydia is shown running on the phone. At the very bottom of the screenshot you can see the iPhone 5 device and iOS 6.1.4 firmware specified.
About a week ago, winocm announced that he had a binary that would perform an untether of the iOS 6.1.3 jailbreak. At that time he had only tested the jailbreak on an iPhone 4.
Update: It looks like winocm was also able to get the jailbreak working on the CDMA version of the iPhone 5 as well.