Pros
A big emphasis on investing in people. If you're a winner, you'll keep winning. All you need to rise to the top is keep being in the top performer pool. Then, it's easier to succeed because you have more visibility and you get first pick of projects. A lot of money. Microsoft has the cash to fund your bold projects as long as the business plan that you propose is solid. The new cafeteria have good foods and ambience. Good benefits, including my favorite of matching charitable givings.
Cons
A lot of mundane work that you need to get out of the way before you have time to look at the big picture and strategize your work. These include a lot of process overhead; there are probably good reasons for them, but they take away time otherwise could be spent on innovation and collaboration. Advice: be really quick with the mundane stuff and spend as much energy as possible on the strategy and prioritization. Everything is kept in SharePoint, and by default permission is denied, so a lot of wasted time finding the right documents and more wasted time tracking down document owners and asking for access. Despite the attempt to turn around the "hero" culture and despite the push for more collaboration, the word collaboration at Microsoft means something different from what I understand it means coming from Silicon Valley. The "hero" culture is in the way. People aren't willing to let go of ideas that they can take credits from even though it's not the best idea. Despite the nominally new performance review system, the old spirit of stack-ranking remains; managers simply change names of what they call the different tiers of performers. The function of how well the company perceives your performance is in large part how much your manager is willing to fight for you and how much political capital she/he has in the calibration meeting. The only true way to transform this culture is to stop the individual bonus and to give bonus at the team level. The number one priority is revenue, not the users, which encourages short-termism and stifles innovation -- or maybe I was on a wrong team.