Microsoft have posted an accumulation of security bulletins for the month of December 2006, an end-user version of security focus can be viewed here and the Protect Your PC website initiative link is also recommended for end-users
Critical
Cumulative Security Update for Internet Explorer (925454)
Vulnerability in Visual Studio 2005 Could Allow Remote Code Execution (925674)
Vulnerability in Windows Media Format Could Allow Remote Code Execution (923689)Important
Vulnerability in SNMP Could Allow Remote Code Execution (926247)
Vulnerability in Windows Could Allow Elevation of Privilege (926255)
Cumulative Security Update for Outlook Express (923694)
Vulnerability in Remote Installation Service Could Allow Remote Code Execution (926121)