Pros
I work in Deloitte's Federal Practice. One of the better reasons for coming to Deloitte instead of a smaller government contractor is the variety of projects and clients across the federal government. The practice is growing at a relatively fast rate, so there are definitely good opportunities to make a name for yourself quickly. Compared with experiences I hear (second-hand) at other companies, I find Deloitte does an above average job of recognizing and rewarding job performance in its employees. The end-of-year review process is very thorough, if slightly prolonged. Deloitte has also done a good job of getting former SES's and high level military officials to work for the firm, adding to the already high brand recognition having Deloitte Consulting on your resume provides.
Cons
Deloitte's Federal Practice feels very separate from the rest of the firm. From recruiting, to training opportunities, to the types of engagements, you sometimes forget you work for a firm that still does the majority of its business with commercial clients. Engagements are typically longer than on the commercial side. It's not uncommon, even at the Analyst/Consultant/Sr Consultant level, to find yourself on a project for a year, or longer. This is not necessarily a bad thing - it forces you to develop some expertise in a functional area or a client. But beware if you are coming here thinking you will be on four different projects a year, as with the commercial Business Analyst program. Senior leadership is definitely looking to improve on this, but there is still much work to be done.