Hot on the heels of the release of the new and improved RedSn0w (featuring George Hotz's limera1n exploit) comes word that RS will successfully jailbreak iOS 4.2 Gold Master. (For those not in the know, the "Gold Master" keyword means that it's still a beta, but only one step away from an official release.)
Now normally, only those in the iOS Developer's Program would have access to the 4.2 GM. Fortunately, we already reported on a way to get around that. (And for additional reading, check out our thoughts on 4.2 after a day of use…)
From the "Caveat Emptor" Department: Think twice about trying this upgrade/jailbreak if your iDevice is already jailbroken, because the risk of losing the existing break is always present. Also, the Dev-Team extends their own cautions, since 4.2 GM is still technically a beta release.