Apple has released two updates - Mac OS X, installer Update 1.0 and
iPod Updater 1.0

Installer Update 1.0 delivers improved support for installing software updates and is required for future Mac OS X updates. It can be downloaded via the Software Update application in System Preferences.

iPod Updater 1.0 is for Mac OS 9.2.1 and above and downloads new software to the iPod. It also offers a Restore command that returns iPod to its factory settings, erasing and reformatting the iPod before downloading new software.