Apple released the developer preview of iPhone OS 4.0 yesterday afternoon. And this morning iPhone hacker MuscleNerd (
http://twitter.com/MuscleNerd/status/11879596721) posted a video on YouTube which appears to show an iPhone running the new operating system with a few extra features enabled such as the abililty to run a VNC client and the Cydia (
http://cydia.saurik.com/) third party app store.
But heres the thing neither of those things should work out of the box with iPhone OS 4.0. And that means MuscleNerd has most likely already figured out how to jailbreak iPhone OS 4.0. For the uninitiated, jailbreaking basically means hacking an iPhone, iPod touch, or iPad so that it can run code that hasnt been approved by Apple.
MuscleNerd isnt publicly saying how he did it. But thats likely because the developer preview is still an early build and things could change by the time Apple pushes out iPhone OS 4.0 to consumers this summer. One thing seems fairly clear though: When that happens it probably wont take very long at all for hackers to release a jailbreak technique for iPhone OS 4.0.
Something you won't find in stock 4.0...a VNC server

Questions:
http://twitter.com/musclenerd &
http://blog.iphone-dev.org . PS: 4.0 BETAS are BUGGY! Don't bother trying them if you're not developing apps for them!