It's funny, I was having the same idea recently while using the JOSM validator
on "finished" areas of TM projects.
JOSM validator already has a big red error category for duplicate buildings
(where there is 100% overlap). This crops up a bit in our finished projects,
but it shouldn't really.
The weekly round-up of OSM news, issue # 383,
is now available online in English, giving as always a summary of all things
happening in the openstreetmap world:
http://www.weeklyosm.eu/en/archives/9731/
Enjoy!
weeklyOSM?
who?: https://wiki.openstreetmap.org/wiki/WeeklyOSM#Available_Languages
