- Security is improved. This update fixes vulnerabilities in Office 2008 that an attacker can use to overwrite the contents of your computer's memory with malicious code. For more information, see the security bulletin that is listed earlier in this document.
- Stability is improved. This update fixes an issue that causes Office 2008 applications to close unexpectedly when you open or use Office 2008 applications.
- Windows Office documents to which metafiles are attached now contain the correct text spacing when they are opened in Office 2008 for Mac. This update fixes text spacing issues that occur when you use Office 2008 for Mac to open a Windows Office document to which an OLE object or a metafile is attached.
While my experience is probably idiosyncratic, I did have a rather nasty sequence of events after updating my home machine to the new Office version: my Entourage database went belly-up and had to be rebuilt. Once the rebuild was done and Entourage was relaunched, more badness ensued; due to a yet-to-be-isolated issue, all of the mail, contacts and calendar entries in my connected Exchange 2003 account went poof and had to be restored from a backup. Not my best day ever.
I'm inclined to believe that this snafu was specific to my bloated database file and my Exchange config, and not something likely to hit most users... nevertheless, you might consider backing up your Office 2008 Identities folder (which contains your Entourage mail & PIM data) prior to the update.