Pros
People you work with are pretty cool and its easy to make friends. Accenture seems to hire mostly hard working people who actually have personalities, which is cool. Projects are pretty diverse and all the perks - healthy vacation time, rewards programs, almost weekly sponsored happy hours, etc - can make for a fun experience. Sr Managers and Execs are usually very approachable and will talk to you about anything. Accenture has a good brand name and hopefully having it on your resume reaps returns later on.
Cons
Pay is pretty good when your first starting out, but subsequent increases have been miniscule. The laddering process for promotions, like many here have mentioned, is prone to bias and not done effectively in my opinion. Your life pretty much depends on like one Sr Exec somewhere who probably hasnt ever worked with you. As an analyst, most of the work is very low level, and doesnt command anyone's repect and attention. Accenture keeps hiring liberal arts/business majors and tries to force them to do technical roles which they dont want to do. Every analyst wants to get into the strategy group, which isnt even that good compared with the industry.