It is not the greatest jailbreak and you have to make sure that your phone is connected to the computer whenever you need to reboot it. It will not automatically install Redsnow's jailbreak software "Cydia" when it is downloaded either. To be fair, redsn0w only had two days to hack it. Cydia is the software which gives you access to most of the iPhone bits and bobs on a jailbroken phone.
But it does not bode well for Apple, which has been playing a cat and mouse game with the writers of jailbreak code. Apple insists that if you buy its products, you are sentenced to stay in its wall garden of delights forever. The jailbreakers think that if you pay for something you should be allowed to do with it what you will.
Redsn0w version 0.9.13 dev 3 is proof that the Apple has not managed to stop jailbreaking in its new version and the cat and mouse game will be part of the iPhone 5's destiny too.
It is a developer version and is not a public release. The group said that there are all the chances that you may encounter certain bugs and instability.
It suggests that Apple users who know nothing about software should not touch it at the moment. Since this is most of them, Apple is safe for now.