Pros
This place values ideas, talent and enthusiasm in equal measure. Your growth is directly proportional to your desire to learn and try new stuff. The company and the people - right from your immediate manager to the CEO are willing to listen to you and are happy to help you grow. Work is challenging and demanding and problems that are handed to you are usually not easy ones - just the right combination to make a job interesting. Generous time off and your managers are encouraging people to take time off to relax and recharge. Seriously, I love my job. And the Friday happy-hours.
Cons
Despite being around for several year the culture is still startup-like - lots of energy and drive to churn out products. Sometime it gets a little difficult to figure out and plan effort, but it's getting better - every growing company goes through this phase, but the sooner you get out of this phase the better.