I came up to Berlin this weekend for the Europe Photobloggers meetup. Before coming I checked on the OpenStreetMap coverage and was amazed at how complete it was. So much so that I didn't really have any way of helping out with the mapping whilst out and about taking photos. Ah well, it did give me more of a chance to take photos instead of making notes about every street we walked!
I can't wait for mobile mapping tools that'll give instant access to (OpenStreet)Maps of the areas around you so you can see what's missing when you're actually there and be able to add in extra bits where necessary :)