The iPhone already has a jailbreak 4S

The DevTeam has released an exploit that you have to jailbreak the iPhone 4S.

This is a userland exploit, in terms of software (and therefore untethered), so the problem is that it is very easy to close, just will need a firmware update for it. The good news is that work on iPad 2 for example, and of course in iPhone 4 and 3G or any device with iOS 5.

Much work to do, but will soon have a untethered jailbreak for all devices with IOS 5. What good news!