Pros
Perhaps the single best place I have ever worked. The way they treat their employees is second to none. There are amazing perks and benefits that are comparable to top tech firms. While they keep you busy the workload is reasonable and work-life balance is actually attainable. The longer you stay with the company the better things get (tenure is rewarded well).
Cons
The company large and very stratified. While this gives plenty of potential for upward mobility you will almost certainly have to put in above average time to move up as there are always a dozen people that have been there "forever" looking for that promotion you want. As a result often the person that most deserves the promotion is passed over for a more know (usually more tenured) person. Compensation is generally good, but they don't pay the appropriate premiums for specialties in software development (ex: JavaScript developers are getting a premium in the market, but they pay them the same as any other developer). Raises between promotions are negligible barely -- if even -- matching inflation.