Pros
A few years resulted in a lifetime of friends, professional connections, experience and opportunities. Accenture provided the opportunity to work through multiple functional departments (IT, Sales, Marketing, Finance for myself) and through multiple industries. This kind of experience in a relatively short time is of enormous value to me in my current position and looking for new opportunities. The professional network I developed has proven as valuable as the skills Accenture taught me, and added to that is that Accenture makes better efforts than most other companies to continue to stay connected with former employees and actively work to connect them to new opportunities.
Cons
At some point, it does become a numbers game. The "up or out" culture is what provides the amazing opportunities, but it also results in far to many good employees leaving out of frustration or lack of a landing point short of Senior Executive. The travel can also be a bit excessive, no one should take a job with Accenture unless they are prepared to be a true road warrior, 48 weeks a year. You might have a run at Accenture with manageable travel for a few years, but eventually you will be on the road for extended periods. If that's not to your liking, don't work there.