I didn't get a chance to meet him, but I'm sure he would've stayed around for anyone who wanted to talk.
My take-away was that its a very inspiring event. So inspiring that I wanted to leave ASAP so I can work on my ideas. Basically, you're in an auditorium learning about how a few of these companies (e.g. https://www.codecademy.com/) got started. Afterward, you may stick around to socialize.
I will say that I didn't necessary learn anything new. But, I don't think that was the point. It was more about getting people excited to dream big and create things that may become businesses.
Here are some videos to watch that will help you get the most out of it - 1. Alexis Ohanian : https://www.youtube.com/watch?v=KKYkmYuk5l8 2. Sam Altman's Course : http://startupclass.samaltman.com/ 3. Apoorva Mehta (Instacart) at Startup School NY 2014 : https://www.youtube.com/watch?v=wkmR7TYUt_c
Good luck!