Microsoft recently issued updates for Office versions 2004, 2008, and 2011, which address security flaws that could leave your computer vulnerable to attacks. This vulnerability is addressed in all three releases, but in addition the update for Office 2011 includes some bug fixes for errors with Word and Outlook.
The updaters can be downloaded using Microsoft's AutoUpdate utility, or can be downloaded from the following locations:
The specifics for the Office 2011 update are that Outlook now handles time zones more reliably so "Free" or "Busy" information shows correctly for people. In addition, the update fixes a couple of situations where delegate information can be lost when managing account settings and certificates. There are also a couple of stability improvements for Microsoft Word, and a fix for wrong characters being displayed when using the Hiragana Japanese input mode.
Be sure to back up your systems before applying the updates.