Sports Illustrated has built a unique Facebook application for March Madness, where Bracketology meets Social Networking in SI’s Bracket Challenge.

The application allows you to build a bracket with your friends to see whose picks reign supreme, as well as the latest news and updates from every team in the NCAA tourney.

To date, over 22,000 people have added the Facebook application. With “Selection Sunday” only 5 days away, that number is expected to rise exponentially.

Other notable features include a “Friend Predictor” that allows you to see which friends have added the app, while offering the option of who you think will do best; “Citizen Sports Fan Breakdown” shows which teams in the NCAA have the most fans on Facebook, and the overall ability to talk smack in over 40 active discussion boards. Leave your poor judgment at the door, kiddos!