Shane today in class was looking for where the SharePoint change log is. I did a quick search and found a decent answer on MSDN with detail on Change Log Freshness…
"The Change Log is a physical table in each content database, and each transaction writes to the log." The Change Log recevied by hitting the lists web service http://<Site>/_vti_bin/Lists.asmx GetListItemChanges with GetListItemChangesSinceToken method of the Lists Web service to get changes starting from a specified point in time."
Found a great WSS 3.0 web service one page quick reference on Look Alive blog which I’m sure came from across the various MSDN pages.
Note: The change log is security trimmed. "The change log returns a list of SPChange objects for changes that happened, for example, to the following object types:
- Items, files, and folders
- List metadata
- Site metadata