Pros
The people at Hub are smart, fun, and do amazing work. You'd be hard-pressed to find a better work environment. Everyone I worked with was self-motivated and had high expectations, so the work was always high-quality the first time around. If you earn it, you can be given a ton of responsibility and take on projects that you wouldn't touch at a bigger agency. The creative team and account team work together incredibly well. The end result of this environment is something special. The office is open (both in the physical sense and in the way that people interact) which creates a great space for creativity as well as for the quality of relationships you develop with your coworkers. There's always music playing, people eat lunch together at the high-top table in the middle of the office, and there is plenty of out-of-office bonding. Work-hard, play-hard is perfectly embodied here. They tend to work with clients they like, so even the relationships with clients are usually fun and open. They trust Hub to do great work, and Hub delivers.
Cons
Expectations are high and the pace is fast. That's just the nature of a deadline-driven industry, and Hub expects everyone to pull their weight. I loved it, but it's not for everyone. Since it's a small agency, people are expected to take on multiple roles and responsibilities. If you like a limited scope of responsibility and separation of job functions, this place isn't for you.