Patch Tuesday for June has arrived, and with it Microsoft is bringing six patches. These patches fix a total of 15 vulnerabilities, four of which have earned the critical rating. The expanded June 2007 Security Bulletin outlines each of the flaws, including some as of yet unpatched ones. Of the four critical flaws addressed, two of them affect Vista.
Of course, updating your systems is always highly suggested and nearly a necessity for Internet-attached hosts. If you aren't using automatic updates, head on over to Microsoft's update center and get patched.