Pros
Employee resource groups to encourage diversity, like LGBT, Women's Leadership, Black Employee Network, etc., nice corporate building with a beautiful gym, great cafeteria with healthy food, health clinic, drug store, etc.
Cons
not good in bad economic times, all training is taken away , performance appraisals and ranking system is military style and pits you against own team mates; too many layers of IT middle management, will throw devs, qa and analysts under the bus to save their IT management jobs; mid-level managers only have small staffs of people reporting to them and those jobs could better go to people in operations that are currently furloughed; if you are dev, you won't get to do the development you enjoy doing because they'll make you spend months doing research work as they believe engineers should be generalists.