Pros
Autonomy- no one is going to tell you how to do your job. You decide the best way. Business process - Amazon has a different way of doing things. Yes, they do write 1-6 page documents to prepare for meetings rather than putting thoughts into a PowerPoint presentation. Then they spend the first 10-20 minutes of the meeting quietly reading it. Yes, they do encourage healthy debate to a level that makes a lot of people uncomfortable. In the end this makes for better business decisions. Mobility - once you've been here for a year and had a decent review, it's very easy to move around.
Cons
Autonomy- no one is going to tell you how to do your job. You don't get a whole lot of guidance. It's sort of trial by fire's Career development - this is pretty much up to you Varying culture - the culture can be vastly different based on the team you're on. It can range from nearly as bad as the media makes it out to be to a fun startup environment