Open Source Activity Map
Red Hat have published the results of a collaborative research project with Georgia Tech to determine the level of use of open source software in different countries. Redhat have produced an interactive Google Map so that the data can be explored interactively.
You can click individual countries on the map to see their ranking and scores. The countries were ranked by overall activity. Europe ranks high in the global index, which lists France, Spain, and Germany as the countries with the highest level of open source activity. The United States came in ninth place.