iOS 5 has been jailbroken within 24 hours of its debut in the iOS dev center. According to iOS hacker MuscleNerd, the exploit uses limera1n and is a tethered boot on the iPod touch fourth generation at this time. Cydia installs fine and seems to work without issue. This achievement is good news for devs who are rocking iOS 5 and those looking forward to the release version of iOS which should land this fall.
[Via