Pros
I have only been an employee at Blizzard for two weeks, but I can already feel the impact the culture is having on me as a person. This will be an experience that will follow me for the rest of my life. There is an immense sense of dedication and pride on the teams, with a work ethic that encourages people to contribute in creative ways. Having come from a much larger (and stuffier) organization, it's certainly a change in pace! Everything is Blizzard culture, and being a nerd and geeking out on your favorite passions is encouraged! I have never been more encouraged to be who I am than I have been since the first day I entered the gates. This is a culture that I can definitely say has been driven from the top down, and I enjoy every minute of it. Not only do they encourage you to be you, be comfortable, but they also encourage you to be healthy. Blizzard spends an immense amount of its resources on helping employees be the best version of themselves (mind, body, and soul). And I think it's just incredible. There is an outdoor volleyball court, outdoor basketball court, outdoor weights, and an indoor gym. Healthy drinks and food are discounted. Bottled water is cheaper than sodas in the vending machines. Salads are rewarded. Walking/biking to work is rewarded. I've picked up a whole bowl of salad + chicken + other stuff for < $5 for lunch! It's just incredible.
Cons
I haven't yet seen any cons to working for Blizzard on a personal level. That's not to say that others may not have an issue, but compared to previous employers I can definitely say Blizzard is pretty freakin' amazing.