Google has announced a new Google Maps feature which allows you to refine search results on a map by 'Neighborhood' or 'User Rating'.
For example, if you search for pizza restaurants in New York you might be given a bewildering number of results. Using 'Neighborhood' you can refine your search by restricting the results to those restaurants in Staten Island. You can further refine the results by selecting 'User Rating' and restricting the results to those restaurants that have been given four stars or above.
I think the 'Neighborhood' option may be restricted to cities in the United States. London, for example, doesn't have this option, although you can still refine your results by 'User Rating'.
Via: Google LatLong: Refine by user ratings and neighborhoods