A much smaller sample, but I've noticed that ElevenSmooth, another mathematical distributed computing project, is heavily weighted with Europeans, also with a wide spread of countries. In pondering why these projects attract Europeans in high proportions, I'm afraid it may be that the abyssmal quality of much of American education, especially in math and sciences, leaves a much smaller proportion of Americans competent to understand the projects. Other times I think it may just be that television babies don't have sufficient attentilon span to work on these projects. Regardless of why, I think it's an interesting observation.