Initially only available for users running OS X, the P0sixspwn jailbreak for iOS 6.1.x has now been updated and made available for Windows users with immediate effect.
P0sixspwn for Mac OS X is out. Follow the instructions on how to jailbreak iOS 6.1.5, 6.1.4 and 6.1.3 untethered on iPhone 5, 4s, 4, 3GS, iPod touch 4, 5 and other devices.