Pros
It's an amazing company to work for, not only are you working for a company that is actually making a difference, but the "culture" is something I have never experienced before. The company really prides itself on its "culture", and reasonably so. Very casual, very fun and everything still gets done. I learned a lot and am looking forward to see where my new skills will take me.
Cons
I think the laid back culture might affect some people's ability to still maintain professionalism in the workplace. There's a work/fun balance that you need to have to work here, and most employees have that. There are a handful, that seem to act like they're in high school again, and play the politics, passive aggressive and resentment game, instead of being an adult and talking things out.