Pros
NS offers a very stable work environment. Stealing or lying will get you fired, but little else will. Benefits are solid. The management training program was rated as one of the 50 best in the US and gives you a good view of the company as a whole. Pay can be extremely rewarding in the later years, minimal at entry level. Yearly profit sharing bonuses. More than 50% of the employees are nearing retirement which means many opportunities for newer employees. A couple corporate retreats are very nice.
Cons
NS is used to the past. In the past you went to work somewhere and committed for the rest of your working years. If you come ready to commit, both to NS and yourself, to 30 years, then you can kick butt. Otherwise, its not for you. Most young employees today arent ready for that. The culture is also reluctant to any type of changes and typically always favors the "way things have always been done." This can be discouraging. Lastly, if you end up with a senior manager who has been around forever and has a "rough, work you to the bone, you kids dont know the first thing about hard work" attitude, good luck. They have been around forever and no one will get rid of them, no matter how poor their management skills are.