Nate Silver, who does the New York Times blog fivethirtyeight (usually on elections, but now on more), did an analysis and reports that the elimination bracket style used by the N.C.A.A. (and debate tournaments) isn't exactly fair:
http://fivethirtyeight.blogs.nytimes.com/2011/03/15/when-15th-is-better-than-8th-the-math-shows-the-bracket-is-backward/
Specifically, it makes me wonder why they don't go to the style used by the N.H.L.: amongst whichever teams are left, top seed plays bottom seed, second seed plays second worst, etc. In the N.C.A.A., fixed brackets style, if the bottom seed upsets the top seed, suddenly the bottom seed now has an easier schedule than it deserves. In the N.H.L., re-seeding style, the bottom seed would have to keep upsetting all the top seeds to keep going.