Kolossos has drawn a Feature Density Map with the GeoNames data set. The bright parts of the map show high density areas sporting a lot of features per km² and the dark parts show regions with no or only few GeoNames features.
Dense regions are Bosnia Herzegowina (1.008 features per km²) , Germany (0.447), North Korea (0.318), Pakistan (0.154) and the east coast of the US.
The dark spots mainly indicate unihabited areas and it is thus interesting to compare the Feature Density Map with the Population Density Map compiled by NASA in 1994 :
It shows that India (0.0114) and China (0.0113) have surprisingly few GeoNames features compared to their high population density.
[more geonames feature statistics]