Software Update: Updates were installed by System Administrator

Occasionally, Software Update pops up a dialog stating "Updates were installed by System Administrator. Do you want to check for additional updates now?" I've seen this message perhaps 5 or 6 times now.

There is no indication of which updates were installed, and the "Installed Software" tab on the System Preferences/Software Update screen does not indicate that any software was installed.

How do I find out what software was updated? Is Apple releasing frequent updates to Lion that are not bundled as a numbered release (for instance, 10.7.1)?

Is there a log of what changes were made to your system?

I've tried searching for this information with no success.

Thanks!

 

If you read my original post, I state I did just that...