I have been asked this many times following up on the blog entry Installing Office 2003 and Office 2007 on the same system where once people have removed the problem with the End User Licensing Agreement (EULA) appearing every time they start Office they then get the dialogs below every time they switch...
I did a quick scan and it seems that this month Office is the main target of updates, along with one critical one for Windows Server (for DNS RPC attack) and one for IE7. Worth a quick download and install :-) I also got this in the mail today: Apple QuickTime 7.x must be upgraded to 7.1.5 or higher...