Jailbreak for iOS 5.0.1
It appears that a jailbreak has been developed for non-A5 iDevices running iOS 5.0.1, but no jailbreak yet exists for the iPad 2 and iPhone 4S, which use the A5 chip.

Note that this is a rather localized answer; it seems quite likely that a jailbreak will eventually be developed, but as of January 2, 2012, this seems to be the state of things.