Foursquare released Foursquare Explore which is an interactive map showing check-ins and relationshships between checkins.
#Foursquare #LBS
http://mashable.com/2013/01/18/foursquare-map/
![](https://lh6.googleusercontent.com/-uklWlIo6KLk/UPmjXIn0e5I/AAAAAAAAQtQ/zhw6FjkL1q8/Foursquare.jpg?imgmax=1600)
IT's more dense on the eastern side of the USA. You should see the vast expanse of the west.
cool