I am Ruud den Blanken and do some mapping around my hometown.
My username is "ruudblank" also for my Openstreetmap edits and Twitter account.
I use my Blackberry with GPSLogger app to log my tracks, and mainly JOSM for updating the map.
I converted data from the national registration for buildings and adresses (Basisregistratie Adressen en Gebouwen: BAG) to OSM-format, but only added a small amount to OSM as a testcase. The municipalities are owners of the data, and therefore I requested my municipality for usage of this BAG data for OSM (request via Wet Openbaarheid Bestuur: WOB). The request is pending.
I stopped adding housenumbers and focus now more on roads, adding details in the tags.