This is late but it's grown tremendously over the past few years. I've gone for 3 out of the last 4 years and this year (2013) was the year I didn't go.
The first year I went it rained which made no one come so I was in heaven. I went from tent to tent, talked to the brewers and got so hammered I had to have a friend drive me home. Stupid imperial beers snuck up on me. In short, awesomeness.
The second year it was good weather and there was a pretty big crowd, it wasn't bad but if you don't like being elbow to elbow you might have a problem with this.
Third year....UGH!!! is all I can say. They added something like 15 more breweries. Unfortunately they kept it in the same space AND added more tickets because of this. What you got was chaos, lines that you'd get your beer, go stand in a line of about 30-50 people. While you were in line you'd get to maybe 10-30 people from the beer and your previous beer has been enjoyed and is gone.
Maybe this is me just getting older and having a bit more money but go to Boulevard's tap rooms and try some stuff there or go to The Flying Saucer or some place in KC that has a good chunk of taps and just try stuff there. The Saucer crew use to know me well (stupid marriage and a kid...I joke) and they'll give you tasters left and right as long as you're good about tipping and talking.