8 patches, five of which bear the dreaded "critical" rating. The link above will take you to Microsoft's advisory on the subject.
Meanwhile, Apple has had to apply another patch to QuickTime. The new version is 7.4.5 and here is Apple's advisory. Once again; media players bite.
Opera also has a new version of their browser out, version 9.27, which fixes two critical security flaws present in all previous versions.
Upgrade and patch at every opportunity. What else have you got to do with your life, right?