Pros
There are a couple of good reasons to work at Amazon. You'll probably see some of the same words used to describe other companies within the tech sector, smart, driven, intelligent colleagues. In general you get to work with smart people. Rarely have I met somebody who was incompetent working there. Inexperienced but never incompetent. For the right personality types, this is a way to experience start up life (wearing multiple hats, frugality) while also having a semblance of security. The company is still growing and Jeff is willing to make bold long term bets even if the stock market doesn't like the expense in the short term.
Cons
If you're looking for a startup, Amazon is not it. It acts like one but you're unlikely to strike it rich. It still has some of that chaotic nature from the hey day of the internet boom. But it is a mature company. For me the biggest thing is the pager, I like most aspects of my job but carrying a pager is really grating on me. We've gotten better but my patience with the pager has starting to wear thin. Not to mention a couple of breakdowns over the years. Amazon is a place where you can lose your work life balance unless you're strong enough to advocate for yourself.