Pros
Lots of freedom to be creative with minimal bureaucracy, excellent compensation package for US employees, good benefits, opportunities to work at massive scale and with very smart people, great learning experience.
Cons
Management does not care about you, working at Amazon feels very transactional. Your trading your time and expertise for money and experience. Sometimes too much change--we experience major re-orgs at least yearly and minor ones quarterly. If your not working in a area with significant investment by the company, you will experience staffing issue, lack of headcount and potential lay offs. Working too long for Amazon could make it difficult to transition to a new company--Amazon culture is very different and many times at odds with what you would encounter in other companies. Its easy to get used to disagreeing with your boss and voicing new idea's in a way that would be political suicide at other companies but at Amazon is accepted and encouraged. Way too much time spent on document writing. Only 8 paid holidays per year.