The Dev-Team Blog was just updated with a new redsn0w version 0.9.6b4 jailbreak (based on Geohot's Limera1n bootrom exploit) for iOS 4.2.1. Unfortunately, iPhone 4, iPad, and newer iPhone 3GS and iPod touch owners won't find jailbreaking as easy as navigating to a website -- the 4.2.1 jailbreak is currently "tethered" so you'll have to reattach to a PC or Mac to boot into a jailbroken state each time your device loses power or needs a reboot. Those of you who rely on ultrasn0w unlock should hold off for now. Good advice for anyone not comfortable
