One way to judge the utility of a base map such as OpenStreetMap is by how well public institutions are represented. To that end, I've taken it upon myself to map all of the public facilities in Arlington, VA. I recently completed mapping all of the public schools (and quite a few private ones). This coming weekend's editathon I'll complete the addition of firehouses, police stations, and libraries. Parks and community centers may take more time and research, as there are many more of them than there are other facilities. But soon, all of Arlington's public facilities/institutions should be represented on the map.