I contribute to OSM in Wisconsin and in some other areas that I have been to. I first heard about OSM when I needed to find a map for something and the Google Maps result was somewhat lacking. I remembered it and came back to see what exactly it was. After seeing an edit button, I registered and started messing around with it. I do lots of work with land usage, and I work in urban and rural areas, though I prefer urban areas (there's always something to work on).