...specific locations is the focus of the patent filing Identifyinglocations. I blogged about that document in A Google Approach...Accuracy. The location repository approach in IdentifyingLocations sounds like a way of following best practices...
http://www.seobythesea.com/?p=1022
...similar user-rated map apps? Not by much. You soar around the map in quasi-street view or birds-eye view, identifyinglocations as the color-coordinated bubble pops up. Red for dining, blue for shopping, orange for "Priceless" items...
http://reviews.cnet.com/8301-19512_7-10289835-233.html