Google have started to allow users to correct their address gazetteer. By searching for your address (I think this is US only for the moment) you will be shown the address marker as normal, but now when you click on the marker you will have the object to edit it and drag the marker to where you think it should be. This sounds to me like free labour on the pretence of better service in the future… a cunning ploy by Google, and one which I will probably join in on when I find a business I’m looking for has it’s marker out of place.
For minor changes it’s an instant fix, but if it’s wildly out (200m or more) the change gets put in a moderation queue.
I’ve been wondering about this kind of thing for a while and it’s nice to see more collaborative mapping happening… now, if we could only convince Google to collaborate on OpenStreetMap.