Pros
Wonderful people - smart, skillful, enthusiastic, dedicated to quality, kind. Wide range of projects, across a variety of industries and business scales. Truly impressive attention to quality and detail. Respect for autonomy and skill. Employees are given significant room to take real ownership of their work. Although the management has its faults, they're generally extremely open and responsive to feedback. Over my two years, the culture changed significantly for the better. The head of the engineering team is a fantastic manager and great person. The top leadership (CEO/COO, most of the team leaders) are smart, quality-oriented, well-intentioned people.
Cons
Although most employees really got along, the community was not actively nurtured by management. Timing and format of feedback could be improved (and has improved). Due to scale of organization, limited opportunity for progression up the "ladder." The mood in the office can swing substantially on the basis of quantity/quality of work.