Microsoft has released 4 bulletins that address several security vulnerabilities.  The patches address the following components/applications (in order of criticality):

MS11-083 - Vulnerability in TCP/IP Could Allow Remote Code Execution
MS11-085 - Vulnerability in Windows Mail and Windows Meeting Space Could Allow Remote Code Execution 
MS11-086 - Vulnerability in Active Directory Could Allow Elevation of Privilege
MS11-084 - Vulnerability in Windows Kernel-Mode Drivers Could Allow Denial of Service

http://technet.microsoft.com/en-us/security/bulletin/ms11-nov

The SANS write up and recommendations can be found here:  http://isc.sans.org/diary/Microsoft+November+2011+Black+Tuesday+Overview....