One solution might be for them to maintain their own error-checked database, and then provide a website and map overlay ontop of OSM, pointing out where the dis

One solution might be for them to maintain their own error-checked database, and then provide a website and map overlay ontop of OSM, pointing out where the discrepancies are between the two. Then local mappers could go around and confirm the corrections. I do think in the long-run OSM will need some error-checking processes if it aspires to be a definitive database. At the moment, I could quite happily subtly mess up a motorway junction in Japan, and most of the OSM mapping software would have no way to knowing not to package it up and send it out. Vandalism is not an issue now, but as the dataset becomes more popular, I think some mechanisms will need to go into place to protect its integrity (particularly for major infrastructure).