Apple's iOS 4.1 update was only released yesterday, but already a potential jailbreaking hack has been identified. More interestingly, according to the iPhone Dev Team, the boot ROM based hack would require a significant change in hardware should Apple attempt to close the loophole; the flaw has been identified not only in the iPhone 4 but the iPad and fourth-gen iPod touch too.
Jailbreaking is the process by which Apple devices are artificially opened up to third-party applications and tinkering that the Cupertino company itself hasn't approved. Usually the identification of a jailbreaking opportunity results in a game of cat and mouse between the hackers and Apple, but there's the tentative suggestion that this particular exploit could have significantly more longevity. No exact timescale for its implementation, but we're told to expect something soon.