Pros
Booz Allen is a great place to start a career. For a fresh out of college student this is fantastic place. Depending on which office you join, you'll have rapid advancement in the beginning from Researcher up to Senior Consultant. There are some perks like travel if you want it, and for those who don't you can request to be on projects that don't have travel. Management is typically pretty good, but occasionally you'll find the politics of Booz Allen raise their ugly head occassionally.
Cons
The current demerger between the Government Business (which will retain the name Booz Allen Hamilton) and the Commercial Business has left some people confused. There is a general sense that the Government side will be fine, but the Commercial side is probably going to be in trouble financially. Also, the biggest recruiting draw for Booz Allen was it's strong Management Consulting Business (competing against McKinsey, Bain, and BCG), which will be gone. Nobody knows how this demerge will impact both companies, and that uncertainty is can't be felt among the staff during the "town halls." Career mobility is often preached by Senior Management, but a very tricky thing to execute. You'll find sometimes that transition plans extend beyond reasonableness, which often causes the transfers to fall through due to delay in transfering. Also, once you reach Senior Consultant there is a bit of a plateau to Associate, it is a bit of "black box" where you don't really know if you are going to get promoted or not.