Pros
You are surrounded by bright people and there is a lot of opportunity to learn about different clients, industries, issues, and opportunities. The environment ,while sometimes cliquie, offers a lot of camaraderie. The benefits are decent and the vacation time is generous.
Cons
The hours are long - not because they need to be to get the work done, but because utilization and face time are important. The "Employer of Choice" is a marketing tool, but poorly put into play. You can voice your opinion regarding what projects you would or would not like to work on but in the end you will just be placed where they want you to be - regardless of where you live. Depending on management you are working with, you may get haggled about justified expenses (e.g. train fare or mileage and tolls). Vacations are expected to be flexible (you may be asked to cancel or postpone). Promotions are far and few between depending on which group you work in.