Pros

Amazon is a dynamic, interesting company with a unique structure. Pay is competitive, but hours are long, depending on your group. Interview for the GROUP you're working for, rather than the company itself. There is some room for mobility within groups, but the longer you're in the same one, the harder it is to move around. Some groups definitely work harder than others, and some make better software than others.

Cons

The hours can be long and the work can be boring (mine was). But again, it all depends on the group you're a part of. It is also clear that some people are just there "putting in the hours" while others really care about developing their careers and the company.

Advice to Senior Management

The structure of the company when I was there was very different than any other place I've seen. The company was structured more as a collection of startups than a coherent entity. This led to very strange internal billing and hour allocation practices. For instance, I wanted to implement a feature for someone who sat next to me (another developer who was a user of our product), but since he was technically on a different team we had to get management approval and so on and so forth for the additional work. What could have been solved with 15 minutes of coding took 3 weeks, several design documents, and probably collectively 10-15 hours of people's time.

My advice to Amazon's senior management - grow up and get over going for the "startup" feel. That worked for the first few years but it isn't a sustainable model for a large company.