Microsoft, what a great place to work.
Pros
Among the best reasons to work at Microsoft are the people you get to work with. By surrounding yourself with highly talented, passionate, and very smart people, you'll find you learn a large amount about making great software. I truly appreciate the work ethic and care many of my co-workers put into our products. We really strive to make the best software we can. Other reasons it is a great place to work include the beautiful Seattle area, amazing health benefits, and the numerous opportunities to get involved with others who share common interests.
Cons
Personally, I'd like to try out a smaller company at some point in my life. While Microsoft is very large, and has many opportunites to choose from in almost any technical area, I'd like to try out the small business scene. The base pay is greater than the average software development job within the US, but by no means is near the top. I do believe however that the bonus, awards, work/life balance, and health benefits do outweight the lower wage.