Well, that didn’t take very long. Less than a day after the iPhone OS 4.0 beta was released to developers, iPhone hacker Musclenerd has already jailbroken it.
So as not to jeopardize a working jailbreak technique before the final iPhone 4.0 update hits handhelds, no one’s talking about the exact jailbreaking method being employed here. I suppose it could be the same Spirit technique that’s being pursued to finally bring untethered 3.1.3 jailbreak to the third generation iPod Touch.
It’s unlikely that any solution this early in the game will last to the final beta, but if the jailbreaking community’s recent efforts both here and in with the iPad suggest that 4.0 won’t stymie hackers for long.