I'm posting this in case anyone is interested (wasn't sure if it should go in the Chicago area tribe or here.)
I am not affiliated with the event in any way. We went the year before last and it was a nice time - very family friendly, good food, good music, etc.
Neat! I know we can't go this year -- but I really want to bring the kids to something like this while they're still young (you know, normalize being veg for them - 'hey look, other vegetarians! neat! Like us!'), and I know I've read/heard about this event before. Sounds awesome.