In the past month, Apple has released a number of Security Patches for Mac OS and Windows that I have not yet mentioned here. All patches are available from Apple Downloads, or see below for more details.
Apple has released QuickTime 7.2 for Mac OS and Windows which addresses a number of security vulnerabilities outlined in this Apple Security Bulletin. To update your Mac, visit Software Update. To update your Windows computer, visit QuickTime Downloads.
Security Update 2007-006 has been released for Mac OS to correct a couple vulnerabilities. If your computer hasn't already prompted you to run this update, visit Software Update. For more information, see the Security Bulletin.
Apple has also released for iTunes 7.3.1 for Mac and Windows. While not a security update, it does correct a possible software problem and enable iPhone activation. To update your Mac, visit Software Update. To update your Windows computer, visit iTunes Downloads.