I stumbled across this article while doing a Google search. It's an article written in 2004 by a college student that analyzes the rise in popularity of DDR. Specifically, as a game that brought people together socially in a way that hadn't been seen previously.

Honestly, if you're a bit bored, it's a great read and it'll definitely make you nostalgic for the "golden days" of this game and its community.

http://www.stanford.edu/group/htgg/cgi-bin/drupal/sites/default/files2/achan_2004_1.pdf