Until now, Google Maps only pointed to items from custom maps and geo-feeds, but now you can find the maps in the list of results. For example, a search for [president birth places] returns a map that shows where each president of the US was born. You can restrict your search to custom maps and GeoRSS feeds by clicking on "show search options" and selecting "related maps". The index includes the public maps created from the "My Maps" interface.
Source:→ Google LatLong Blog