This update fixes extremely important issues and also helps improve security. It includes fixes for vulnerabilities that an attacker can use to overwrite the contents of your computer’s memory with malicious code.
The patch includes all of the improvements in their previous two updates. The update requires Mac OS X 10.5.8 or later, and is available through the AutoUpdate feature within the office suite, or through direct download from Microsoft.
There you have it – three significant security patches in the course of a month. I guess that’s why Patch Tuesday is such a big deal among users of Microsoft products…