Pros
Awesome, cutting-edge clients to work with. Fast-paced and exciting work environment. Hard work and results are immediately recognized and rewarded. Staff is made up of hard working, fun, and down-to-earth people. Some people gripe that you have to "play the PR game." There is no game--if you work hard, be proactive, and get results for your clients, your work will be immediately recognized by management and you'll be able to move up the ladder quickly. Even though most people are really busy, they are still accessible--even the CEO and President--and will make time to help you with any questions you have. Management seems to be serious about boosting office morale and retaining employees long term-- they are working on events like trips to Giants' games, monthly happy hours, and more career development opportunities. The company really does feel like a group of friends that happens to be working really hard and collaborating together.
Cons
It can be stressful at times, but that should be the case at a thriving agency. It can be hard to define the right work/life balance. There can be some office politics, but that happens everywhere. The high turnover can be unsettling and create instability on some accounts, but management looks to be trying to change that and keep employees long term.