I'm sure many of you have seen this, as it has been making the rounds this week on the interwebs. I've been working on some other research and missed it until Mark Driscoll emailed it to me (thanks, Mark).
The New York Times has produced an interactive map of America that allows users to browse data from the Census Bureau's American Community Survey (based on samples from 2005 to 2009) in specific neighborhoods. The website says, "Because these figures are based on samples, they are subject to a margin of error, particularly in places with a low population, and are best regarded as estimates." Nevertheless, this is a helpful (and cool) tool that offers some good information on your city and the neighborhoods that make it up.
Churches and church planters in particular use websites like city-data.com, or get specialized research of their communities through their denomination or network, to better understand the makeup of the people they are seeking to reach with the gospel. If you want to weigh in, I wonder: Are you using any tools like this to better understand your city? How have you found such demographic research to be helpful in your ministry?