Pros
Great experience: you learn a lot in a short period. You are given significant responsibility once your immediate project manager has confidence in you, and it's up to you to build from there. The work you do is relevant and more concrete than what you'd find at many other consulting firms, although you initially have little say in which projects you undertake (and once you do, you may be specialized in an area you would not have initially pursued). It's a good name for a resume. People are generally very smart and amiable, and the atmosphere is collaborative.
Cons
Burnout: since the recession, hours have noticeably increased and the job has gone from intensive to overwhelming. You don't want to calculate your implied hourly wage. You get significant PTO, but many individuals struggle to take time off and only do so once they've 'maxed out' and will lose it at the end of the year. Work-life balance, in summary, is atrocious. I know several senior people who have missed the birth of children to put out project 'fires', and personally, I am expected to be available and checking email 24x7 (it's the first thing I do in the morning and last thing I do at night, including weekends). Also, the annual review process leaves something to be desired; tenure sometimes outweighs merit in promotion decisions.