Some interesting demographic data for main space edits to our largest Wikipedia projects may be found at http://meta.wkimedia.org/wiki/Edits_by_project_and_country_of_origin.
My thanks to Greg Maxwell for his invaluable assistance generating this data.
Some observations * NL and BE are language sluts. * ptwiki gets quite a bit more edits from BR than from PT, although almost 75% of edits from PT are to ptwiki. * MX has a depressingly low participation in eswiki.
Not reported in the data on the page, but possibly of interest: US accounts for 27.61% of edits to the projects sampled, followed by DE at 10.01% and GB at 8.15%.
Kelly