Pros
Stability is number one here. It's a steady job that, at least in my department, allows for a personal life. I have plenty of time off. They compensate well and there are some great benefits (matching 401(k), company stock purchase program, pension (it's not the same but it's still a pension). I work with some great people. There's nothing cut-throat about it.
Cons
Beaucracy. There are endless policies and procedures. Depending on who you work for, there is sometimes a lack of trust in employees. The idea that I'm not working unless I'm stuck in my chair for 9-10 hours a day is archaic. Change is almost impossible because the culture is very old-fashioned with an almost military attitude in it's operations. The motto should be changed from "ON IT" to "IT IS WHAT IT IS". People sometimes seem to go along to get along. Management tends to do whatever upper management wants because they are afraid to stand up to them...perhaps because some of them are exhibit sociopathic behaviors. Promotions are heavy with cronyism/nepotism. Compensation is not always balanced (underperformers getting the same or better compensation). The Company doesn't utilize it's talent. The candidates are pre-selected in many instances but the HR policies let management get away with it. For every career development position, they step on someone else's career. Promoting people who are not qualified are resented by the people who are qualified.