This is awesome. Great idea and really well executed. I'll fill my bracket out tomorrow.<p>WRT getting people to come back, I'd leverage your stats. Some ideas:<p>* Tweet during the tournament. e.g., "63% of our users correctly predicted Georgetown over Tenn."<p>* Tweet / show on the site the percentages of people who bet each way on each game, and the percentage still left in the running<p>* Show the user their potential chance of winning the $5k over the course of the tournament, as people are eliminated. Like watching poker on TV.<p>* Show a leaderboard and tweet the current leaders. Have many categories, e.g., "top picker this round", "top overall", "worst overall"<p>* Tweet / blog interesting stats you see in the dataset. For example, which team do people think is most underranked? Overranked? What team do people think is the absolute worst? Absolute best?<p>* What does your aggregate Final Four look like? Aggregate Sweet 16? Track the "score" of the aggregated bracket over the course of the tournament.<p>Edited to add:<p>ESPN does something really clever with Fantasy Sports you could mimic. During the football season they'll run ads for a "late league", for people who missed the draft deadline. If you offered a "late pool" (i.e., one that starts in the round of 32 or 16) I bet you'd be the only one.