Pros
Company is heavy on tech savvy individuals. They constantly strive to develop their employees to re-think their current level of thought and learning by challenging them to expand their knowledge base with new means to expand their willingness to "be right a lot." They have a high hiring bar, and those who do meet those expectations work to meet expectations to become permanent employees. Amazon also encourages constant reevaluation of their practices by all employees, in the form of weekly meetings in which a team member can suggest changes directly to the management team. Also, Amazon recruits from a wide variety of disciples, not only technical, which I personally feel is a huge positive.
Cons
The learning curve can be difficult at times, but due to the high level and intellect of the employees, it is easily adapted.