The Dev Team confirmed earlier today in a blog post that they will not be releasing a jailbreak for iOS 4.0.2. The last jailbreak released was JailbreakMe, which allowed a quick and easy jailbreak directly from the Safari browser, taking advantage of a security hole in the way PDF documents were handled. The patch has now been fixed by Apple with the recent release of iOS 4.0.2.
Dev Team Confirms There Will Not Be a Jailbreak for iOS 4.0.2