Pros
Global company with the opportunity to work on large projects and huge, renowned applications used by 10s of 1000s of people+ Access to great hardware and tools. Often a high degree of autonomy, but that may differ from office to office.
Cons
Lots of poor decision making - i.e. making a decision without understanding the impact; trying to implement global change without a strategy. I've never worked anywhere with so many politics. It depends on who you work for and who they work for as to whether you can be given a raise or a promoted. The standing of an office depends on the products it produces and how they are valued. There's a lot of posturing going on because: multiple teams are developing competing products or services (which shouldn't be happening); because acquisitions have been made of poor products but backed by senior people who do not wish these bad choices to be highlighted. I've seen people sidelined or fired for saying the wrong thing, defending the wrong team, or for being associated with the wrong product. Generally the levels of management make enacting change or having an impact can be impossible. Given the scale of the organisation there is a lot of waster and a lot of poor execution of the vision of senior management. The company is able to make huge mistakes and survive because it has a monopoly on many areas and is making such a huge amount of money, where a smaller company would crash and burn. It can also be lost in translation as to which team is responsible for a success or failure and much of that is by design.