Google already provides geocoding of danish addresses, why another geocoder? First of all, it's a matter of history. The original GeoAPI.dk geocoder was made before Google started supporting geocoding of danish addresses. Second, GeoAPI.dk is without restrictions to the number of operations that can be performed. This makes GeoAPI.dk a good fit in many cases.
GeoAPI.dk is developed and run by Pragmatics.dk. If you want to get in touch, you can find contact information on the homepage.