I think it has something to do with basketball and March Madnessbut could it be for any tournament?
yea in your case, its msotly pertaining to march madness but the bracket champ is the team who wins their bracket. and yea, any tournament can have a bracket champ.
It is about March Madness, and the brackets are used to keep track of who is winning-they use them in a lot of competitions, but the term 'bracket champ' is pretty specific to March Madness and college basketball.
I bet you're talking about the free Facebook gift. Brackets are what's used as a chart to measure the progress of competitors in a tournament. A bracket champ would pertain to the winner of that competition.