Apple released the iOS 4.1 update for iPhones and iPod touch devices yesterday. The update brings the Game Center and fixes that are nice to have. For those who run their iPhone jailbroken there is already good news. The Register reports that iPhone Dev-Team member pod2g was first to announce that there is an exploit in the boot ROM of iOS to jailbreak iOS 4.1.
This new exploit is apparently very deep down and hard to fix for Apple without changing the hardware of the iPhone. The famous browser based Jailbreakme for instance used a browser security hole that Apple could fix rather easily.
There is no jailbreak tool available yet that uses this boot ROM exploit, but of course the iPhone hacker community is working on it.