Pros
Brand name of firm - good leaping point into other careers. Most of the people who work here are solely here for the short-term (5 - 6 years). They want to make manager and then leave. On the whole the people you work with are very smart - in accounting; not necessarily in other life matters. There's also a good mix when it comes to diversity; especially in big offices. Managers/Partners are fairly accessible and they are usually nice people to talk to; though some of them can make your life miserable. There's also a lot of emphasis on accountability; which can be a good or bad thing depending on the situation. The trainings and seminars are awesome and make you feel like the firm really wants you to learn.
Cons
Long hours - and you have to deal with incredibaly inconsiderate seniors/managers/partners. Also, if you're international in outlook and have travelled outside of the U.S.; or if your dream isn't a nice four bedroom house in a quite suburb with a minivan and a sedan parked in the driveway; you should probably stay away from Fed Tax. The people who work here; while they are nice - are some of the most closeted folks I have ever met in my time in America. Most of them have never travelled and look at anything you'd like to share about your culture/food/life with suspicion and this belief that "if it isn't American, it's no good". It does take a lot of getting used to; and if you aren't into baseball/football 24x7; look elsewhere!!