I love openstreetmap, the idea has influenced me greatly. Obviously, I have made very few edits. That will change one day in a big way - I work with MapStory, a similar organization, and I would like to one day help set up a “seamless data commons” where data is automatically pulled and authenticated in each community. We are putting together data from across the world for MapStory Local, a global map of the history of human settlement, and all of that will one day be in OSM.

Read about MapStory Local here: http://thenittygritty.org/mapstorylocal

Developing a seamless data commons: http://wiki.mapstory.org/wiki/MapStory_Local#Appendix_7:_Developing_a_Seamless_Data_Commons