Hi,
I'm facing a problem with the precision of latitude and longitude data in France.
It seems that lots of small cities have the data of the "biggest" city in the neighboorhood.
I have an excel file which contains accurate (or at least more accurate) data for about 34,000 French cities.
Might such a file interest you in your project?
Most of the geonames lat/lng for France are from a US army data set (nga) and are rounded to the minute which results in the pattern you can see on the geonames map view.
We would certainly be interested in having more accurate coordinates and it would be great if you can contribute your excel file to the geonames project.