Hi Im member of the german openstreetmap division and would like to ask if you see potential for cooperation with our project.
OSM provides free geodata that could be rendered in different ways. The technical aspect is an OSM XML communication protocoll and a evolutionary wiki based datadescription.
http://wiki.openstreetmap.org/wiki/Using_OpenStreetMap
http://wiki.openstreetmap.org/wiki/Develop
http://www.osm-3d.org very intersting for you.
With kind regards Matthias
http://wiki.openstreetmap.org/wiki/User:!i!