How to view Software Update history? In OS X 10.8, for system updates that were installed without being signed into an Apple ID, how can I view the update history?

I looked in Library/Logs for an update log, and also in the Software Update for an Installed Software pane, but I don't have either.

Where can I see the updates?
It can be found in an easy to read format using the system information app:

System Information.app > Software > Installations

System information can be found in /Applications/Utilities/System Information.app or via Spotlight.