What happened in May 2007?

I could see Yoville, Mafia Wars and Farmville drawing a lot of people, but I agree the drop you're referring to was remarkably sudden. Obama announced his presidential campaign in February 2007, and that campaign attracted a lot of young and tech-using people - iow, the same sort of volunteers as Wikipedia. Still, we may just be seeing a typical peak-then-plateau as the novelty wears off. As for any userbox flap, I never was aware of one. I just copied mine whenever I found one I liked on someone else's page. ;-) Flatterworld 05:40, 14 March 2011 (UTC)

I'm not convinced by the Obama campaign argument. This has been a global dropoff involving not just EN but language projects with few US based editors. A US specific fall would disproportionately affect EN wiki editing.