UPDATE: Bracketology has been taken off the articles for deletion list.
I guess technically there really isn't a term to describe what me and 50 other people do over the course of a college basketball season but the most accepted word is bracketology which has its origins from Joe Lunardi at ESPN.
Obviously, the concept is very popular and rightly deserves its own Wikipedia page at http://en.wikipedia.org/wiki/Bracketology. However, there is a push to delete the page off Wikipedia. It is, as you probably know, a community-run site. If you would like to add your voice to the discussion, go to the page above and click on the links on top. Keep in mind it isn't a majority vote on whether or not to keep it, rather a forum for discussion with a decision made on a later date.