Full details of this month's security update can be found here.
It's a significant update as it includes updates to address nine critical vulnerabilities and three important vulnerabilities. Ten of the vulnerabilities are for Microsoft Windows, two are for Microsoft Office. It's interesting to note that the severity of the vulnerbility is greater for older versions of Microsoft Office.
The Microsoft Security Response Centre (MSRC) have posted an interesting entry about August's security update.
SANS ISC has some good resources too - http://isc.sans.org/diary.php?storyid=1573&rss