I saw this back in Dec 2010, but couldn't run it on my Mac due to browser issues. I tried it again in March 2011 and found that it worked with Google Chrome, but still not Safari:( Very cool tool!
Provides a wide-ranging audience of persons interested in American history - including historians, other social scientists, teachers, and students - with graphics portraying the demographic history of the United States, as shown by the decennial census of population.