Managing the WSUS Automatic Updates Client Download, Install, and Reboot Behavior with Group Policy -- Bobbie Harder [WSUS PM]
Managing the WSUS Automatic Updates Client Download, Install, and Reboot Behavior with Group Policy (Published: May 4, 2006)
Bobbie Harder [WSUS PM] has recently published an article on Security Guidance in Microsoft Security Newsletter - Volume 3, Issue 5. This is a MUST reading for new WSUS Admins.
http://www.microsoft.com/technet/community/columns/sectip/st0506.mspx