Have you seen any good examples of applications (web or desktop) that make it easy for a user to identify and merge duplicate contacts or other records? We need our users to manually approve the merge rather than leaving it to an automated process.
An interesting pattern we are considering adapting is that of Xero's bank reconciliation. We would display newly created contacts on the left half of the screen and on the right display possible matches from existing older contacts. The user would then have the option of merging the new into the old or designating the new contact as a new and distinct contact. We see some similarities with the process of doing a bank reconciliation, as in a reconciliation you are matching new data (the bank statement) with your existing data (transaction details previously entered). What's interesting is that Xero have tried to actually make this process 'fun' and have succeeded by and large.
I'd love to hear any suggestions of other design patterns or apps we could look at.
Links to screenshots of how Xero works are below and more information on their reconciliation process is in their help documentation or you could register for a free trial to see how it works in person.