I just run Windows Update in Vista and it’s ready to download and install Microsoft Office Compatibility Pack Service Pack 2 (SP2).
Read about the fixes at http://support.microsoft.com/?kbid=953331
Download manually if you plan to install later: http://www.microsoft.com/downloads/details.aspx?FamilyId=4F97AB2F-1F7D-49A3-9123-7CA3E703B916&displaylang=en
There are many HELP file updates also:
Edit: I just found their press release on the above: Office Service Pack 2 A Significant Stability, Performance and Interoperability Upgrade