Per the security bulletin update August 20th:
"This security update resolves three privately reported vulnerabilities in Microsoft Office PowerPoint and Microsoft Office PowerPoint Viewer that could allow remote code execution if a user opens a specially crafted PowerPoint file. An attacker who successfully exploited any of these vulnerabilities could take complete control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights."
If you got the update from Microsoft Download Center
If you MANUALLY installed the Microsoft Security Bulletin MS08-051 – Critical by downloading it from the Microsoft Download Center then you need to download a new, updated version. The initial packages that were released to the Microsoft Download Center earlier on August 12, 2008, labeled Version 1, contained incorrect versions of the binaries.
If you got the update from Windows Update or Office Update
If you got it from Windows Update or Office Update, YOU'RE FINE you do not need to take any action.