Pros
Accenture is a great brand name for IT. From what I've seen it's a great launch point to industry positions but not much else. There's also great camraderie amongst members on the IT side of the business when they're on long engagements (1+ yr). Hours can be very long at times but if you find a great senior manager on your team then I've seen a lot of people happy.
Cons
Accenture is ultimately a tech consulting/outsourcing company. Always remember that. They may have other groups such as their strategy practice but ultimately the dollars come from IT consulting. Therefore if you want to really progress in your career it better be in that area because that's where all the big engagements occur. Promotions are a very political process as they are with any company. As much transparency as they want to bring to the roundtables there's always an X factor that doesn't explain why someone got promoted and someone else didn't. That's a common frustration. Also you'll feel like you're 120% utilized but then the overall utilization rate will be low and there are panic attacks about who's on the beach from management/hr. Someone is billing to admin codes all the time and though this isn't possible it feels like management has no idea who is and punishes everybody.