Apple has released a minor iOS update 4.3.4 which fixed the PDF exploit which was widely used by jailbreaking applications.
Apple's iOS 4.3.4 software update simply lists: "Fixes security vulnerability associated with viewing malicious PDF files" as the improved elements of the new version. The PDF exploit was known to be used by the Jailbreakme.com jail breaking site which allows installing of non-approved Apple software.
However less than a day after the release of the update, Redmond Pie revealed that iOS 4.3.4 had already been jailbroken on the iPad, iPhone and iPod touch. The site went further and offered a bundle of 'Pwnage Tool' software and a tutorial.
As yet the iPad 2 has not been addressed but with Apple and hacking enthusiasts playing a continued game of cat and mouse, such a hack can't be far off and likely neither will be the next Apple update in answer.