Adrian Holovaty is not a sports fan, but I am. Thankfully, he's done quite a service examining NCAA brackets posted by various online publishers such as Sports Illustrated, FOXSports.com and ESPN.com.
Given that these brackets are big moneymakers for these guys, or at least big traffic generators, a good usability study of brackets as interfaces would probably provide some interesting results.
One thing that always irritated me about them, is that they never supported incremental construction. For example, I like to research one regional, fill out the bracket, research another regional, fill it out, etc. These things never have a concept of saving your current state, which is pretty bad considering how much information you have to provide.
Memo to self: get working on your brackets!!