I just got RTCD working great on my network. I have a group of interested parties who the emails will be going to now but the email report is lacking who actually made the change. With the current model of "detect change then download config" its possible that multiple changes could be made by different users so the "Last change by" is not idea for detecting who might have made the changes.
Cisco has a better method for this.
Configuration Change Notification and Logging - Cisco Systems
I think that using the archive feature would be a great improvement to RTCD and allow the reports to include what was changed and who changed it on a per-session level rather than just downloading and comparing the entire config.