Hi,
I have set up a DIDOK compare map on http://didok.osmd.ch/. For those who don't remember, in 2009 we imported the public transport stops from the BAV (http://wiki.openstreetmap.org/wiki/EN:Switzerland/DIDOK)
The compare map should give you an idea about: - potentially missing stops in OSM: there is a new DIDOK list every year. I use now the one from 2012. If you can't find a DIDOK stop on the ground, you can mark it as invalid on the map. - still existing OSM data for potentially deleted stops. - large deviations of OSM and DIDOK. But almost always OSM is right (except the nodes which are still from the initial import of 2009, and were corrected in the mean time in DIDOK, but not in OSM)
If you use the coordinates from the DIDOK compare map, please mark it in OSM as source = Bundesamt für Verkehr (BAV), DIDOK 2012
The map is updated hourly. I hope this is useful, but use it with care. The DIDOK data is known to be terrible in certain areas. Use it to plan your next survey, or find out the correct uic_ref number or uic_name. But don't copy blindly from DIDOK.
Michael