We took our son there when he was less than a year old and he loved it. We loved it as well. The other parents were warm and welcoming as was the staff. The kids learned sign language, spanish, fun games and songs and it helped our little one go down for nap easier after exerting all of that energy. We loved it, especially for the winter when you're stuck inside and don't know what to do with your little one.
I also noticed that you're in Oak Park too. Have you been to the main library yet? It's fantastic! They have all sorts of activities for the kids. We have our son in a reading club now where he wins awards for every 24 - 15 minutes of reading with the family.