My digital collections co-workers (non-map) are talking about an interface called "ViewShare" which organizes digital collections. "Allow users to experience your digital collections". The website shows some kind of googlemap-like app on their sample screenshot.
I will miss the free webinar demonstration because it is the Monday returning from Midwinter. If you are not going to midwinter, maybe you would be interested in sitting in on this. I'd be interested in hearing a geo-literate person's opinion.
http://blogs.loc.gov/digitalpreservation/2011/12/free-online-viewshare-workshop-sign-up-today/