Update: It turns out there’s no need to worry. The owner of the site has transferred ownership of the JailbreakMe.com domain to Saurik, the developer of the Cydia Store for jailbroken iOS apps and the guy who has been hosting the JailbreakMe website all along.
Up until recently the easiest way to jailbreak most iPhone, iPod touch, or iPad models running iOS 4.3 through iOS 4.3.3 was to visit JailbreakMe.com in the mobile Safari browser on your device. From there you could tap a button and your device would download a corrupted PDF file which could insert code on your device and open up the operating system to let you install third party apps that aren’t available from the App Store or make other changes.
The web-based jailbreak utility doesn’t work with newer versions of iOS… at least not yet. But it’s still an impressive tool. Or it was until this morning when the domain was sold and the new owners took down the jailbreaking tool.
According to iPhone Dev Team member @musclenerd, the new home for the web-based jailbreak tools will be jailbreaks.me. Until that site comes online, the easiest way to jailbreak an iOS device is probably to use the latest version of redsn0w — which also supports newer versions of iOS including iOS 5 GM.
Even if JailbreakMe.com does start working again, you should probably avoid using it. As mentioned above, the way you jailbreak an iOS device is to find a security hole and exploit it using a corrupted PDF or some other method. Theoretically the new owner of the website could place malicious code on the site.
There’s no indication right now that this will happen, but it could happen. Then again, the only thing that keeps the jailbreak tools from the folks at the iPhone Dev Team reasonably safe is the fact that they’re tested by hackers that have earned the trust of the community by consistently releasing software that hasn’t broken too many iPhones or stolen anyone’s data.