Contributed By: Cliff Hobbs [MVP SMS]
Reproduced from the Microsoft Software Update Services: Frequently Asked Questions web page:

http://www.microsoft.com/windowsserversystem/sus/susfaq.mspx#top

"SUS is not intended to serve as a replacement to other enterprise software distribution solutions such as Microsoft Systems Management Server. Many customers are using solutions like SMS for complete software management, including response to security and virus issues. Such customers should continue to use these solutions. To improve the Systems Management Server experience, Microsoft released the SMS 2.0 Software Update Services Feature Pack in the third quarter of 2002—adding security patch improvements and enabling you to determine which computers need software updates."