I've put out an updated version of my duplicate detection solution, mainly because of the changes to auto save that came about in UR2. Specifically in organizations where auto save was turned off data was getting saved in the event the user navigated away from the record. All should hopefully be well now. I've also changed the behavior when viewing a potential duplicate record to display in a new window rather than navigating away from the record.
If you are still on v220.127.116.11 I encourage you to update as there has been a few other fixes along the way.
Hopefully in the near future I'll be implementing fellow CRM MVP George Doubinski's idea of a "real-time" display of potential duplicates via a web resource or form notification.
Get the download from CodePlex: