Its "old" data, but probably still relevant.
http://geonames.wordpress.com/2011/02...
They obviously know what they are talking about...
Press Coverage and Quotations
Programmableweb 23 May 2012 - GeoNames most popular API
TechCrunch 26 May 2007
Linuxworld Dec 2006 put geonames.org on a list of "Ten Web 2.0 APIs you can really use", just behind googlmaps : The GeoNames database is one of the best available, based on multiple data sets, and it uses a liberal Creative Commons Attribution license for its data output. It's also quick and responsive.
Sir Tim Berners-Lee : This is a tremendous set of data you have there.
Nature 13. Feb 2006 : ... we hope that database providers will support initiatives, such as the GeoNames Forum.