Pros
You will learn what it really means to be customer centric. Company is much less bureaucratic than other large tech companies. If you are smart, motivated, single and have no other commitments you can succeed. You will learn a lot and ship a lot. It is true that 1 year experience at Amazon is equivalent to 2 years at any other large tech company.
Cons
Company is customer focused, not employee focused. Management does not care about you as a person. If you have kids and your wife is working, then Amazon is not for you. A lot of churn in many groups. Plans, designs and everything else changes all the time. You have to be good at handling such churn. A lot is expected from you. You need to be able to handle a lot of stress, be great at multitasking, and should be available round the clock (e.g early morning meetings with Europe and late night meetings with teams in India).