Pros
Good compensation, collegial working environment, fairly professional management. Work is fairly interesting when you actually get to the core of the job. (See "Cons" about this.)
Cons
Extremely bureaucratic - difficult to get things done. Extremely "vertical" - there are "tiers" of service and benefits, and double standards in conduct and professionalism depending how senior one is. Lots of silly BS corporate-speak like insisting on calling employees "colleagues." (Kind of like everyone at Wal-Mart is an "associate." Dumb and insulting.) The environment is subject to a lot of "change just for the sake of changing things." Senior management talks about evidence-based decisions, but in reality things are changed on a whim or even in the face of contrary evidence. In IT, it is very very difficult to advance unless you go the "people manager" track. Technical expertise is not especially valued, although again as I said in "Pros" people are pretty well compensated. That said, benefits have steadily eroded over the last 10 years.