Microsoft has released several security bulletins today:
·IT folks can get more information at http://www.microsoft.com/technet/security/bulletin/ms04-oct.mspx
·Home users can get information at http://www.microsoft.com/security/default.mspx
It seems that only 1 of the bulletins (MS04-038) affects users who have Windows XP SP 2 and Office 2003 SP 1, although don't take my word for it -- check the bulletins yourself! If you are running an older version of Windows or Office then you may have more updates to install. There is also an Exchange update today.
You can go to Windows Update and Office Update to check for the required fixes, although they may not have propagated through to all the servers just yet.
Of course, you should also have Automatic Updates turned on, which will download and install the Windows patches for you (but not the Office patches :-( ).
You can also sign up for the bi-monthly security newsletter, or subscribe to the security bulletin RSS feed.