Earlier in the week the iPhone Dev Team released a website that allowed users to jailbreak their iPhone, iPod Touch or iPad. The process involved exploiting a vulnerability in the PDF viewer of Apple's mobile operating system. The same vulnerability used to jailbreak the iPhone could allow malicious websites to install software to an iOS based device, gain root access, and then access any part of the system. Thankfully, there are no known malicious exploits out there yet, but the issue itself is a pretty scary thought.
Apple is said to have a patch ready that will plug the security hole, and it will be released in an upcoming iOS update.