Pros
Great people, widely-used products, great compensation package, job security. You can work your own hours. The people you work with are smart go-getters who will do what they promise. When you add up the stock grants, the bonus, the ESPP, the 401(k) and the superb health plan, there aren't many better places to work. If you're in your thirties or forties, and have a family to raise, Microsoft is for you. You'll have financial security and still get to see your kids grow up.
Cons
Slow-moving, bureaucratic company that is rapidly turning into IBM. Microsoft has forgotten how to produce great products, and the company doesn't begin to understand the 21st century marketplace. It's essentially surviving on the continuing profits from its Windows and Office glory days. The sort of people who work at Microsoft are the sort of people who crave stability and security, rather than creativity and challenges.