This visualization, from Foursquare, nicely illustrates the travel chaos that many in the U.S. will experience over the next few days (as if anyone really needed reminding).

The data was collected as Foursquare users “checked in” at different locations between Halloween and New Year’s in 2010. Click on the image to see a larger version and a timeline that shows spikes in activity just before Thanksgiving and Christmas.

While the graphic doesn’t reveal anything particularly surprising about travel on Thanksgiving, and the picture is inherently limited because Foursquare users are just a small slice of the whole traveling population, it does highlight the vast amount of social data that many companies are now collecting, which can be mined in various ways.

Another cool example is the Facebook data revealed yesterday that shows there are roughly 4.75 degrees of separation between users, rather than the six that Stanley Milgram proposed in his famous 1967 paper.