PUBLIC MARKS with tags search & format

Gisgraphy is a free and open source framework that provides fulltext search and find nearby services for places on earth (aka : toponyms) from several databases (aka : gazeteers) on the Web (mainly Geonames, but not only : ESRI for instance). It provides an importer to inject the data into a strongly typed Postgres / Postgis database and use them via 2 webservices or a java API : geolocalisation and fulltext in many format (XML, json, PHP, ruby, python, Atom, RSS / GeoRSS).

OpenSearch is a set of simple formats for the sharing of search results. Any website that has a search feature can make their results available in OpenSearch™ format. Other tools can then read those search results. For example, here is an aggregator tha