I'm working out the errors that the JOSM Validator show me at México City, first, nodes near roads and roads not connected, there's lots and lots of them.
I have a lot of patience and are for the long run compromised with OpenStreetMap but I can't see the end of this errors in the near term :-s

Cheers to the people that made that we can use Bing Maps in OSM (in JOSM), this has done my map editing a lot easier.