Pros
Basically an ideal work scenario - chill environment, filled with snacks (even alcohol), coffee machine, massage chairs, video games, unlimited holiday and flexible hours. The office is relatively young and social too! Management are very open to feedback and great at giving them with respect (at least in my office). Fairly drama free too (at least in my office). Overall - if you are new to the company, you will have a blast - especially if you're coming from the typical 9 to 5, 40 hour workweek company with 25 day holidays.
Cons
The core product, in my opinion, has really taken a backseat over the years in order to diversify the platform's services. It increasingly became difficult to sell because the reputation of the product also regressed. When I started, I was incredibly confident about our ability to make publishers more money compared to other ad-providers. By the end of my tenure - we barely outperformed Google Adsense.