The iPhone Dev-Team has just released Redsn0w 0.9.15b1 for both Windows and Mac, bringing a long list of improvements, including the official version of Cydia on iOS 6.
The updated app comes with support for tethered jailbreak of iOS 6 on A4-based devices, but it can work with virtually all A4 processor-based devices, such as iPhone 4, iPhone 3GS and the fourth-generation iPod touch.
Other units, including those equipped with an A5 processor – iPhone 4S and iPad 2, A5 – iPad 3 and A6 – iPhone 5, are not supported for the time being, but new updates are expected any time now.
Last but not least, the new jailbreak app automatically recognizes your installed iOS 6 software and downloads the necessary jailbreak files all by itself.
The download links are available on the official iPhone Dev-Team page