Pros
-Awesome coworkers; They keep a really high bar, at least for SDEs. Ownership is a real thing; not just management-speak. Every SDE gets to own the entire service/product and has insight and input into every step - requirements gathering, design, development, deploy and maintainance. This is particularly true in new or relatively young services. Each service is also independent of each other. In most aspects, this leads to a startup culture within the big organization. At the same time, being a large organization allows great shared platforms and technologies to be used by all the mini-startups within the company.
Kontras
Lots of management hires from outside the company recently; a recent trend is to crowd out engineers out of meetings. Not sure how it is going to impact the culture long term. Another big con is the compensation. Performance reviews and compensation revisions don't go hand-in-hand. Compensation change follows a really opaque process; with the end result being most pay hikes are paltry, even with great perf review scores. Only saving grace is the stock grant you get on joining and vests over 4 years. That is why so many people leave after 4 years - there is big drop in effective comp at the end of 4 years. In short, if you are joining Amazon, remember that you are basically negotiating salary for 4 years; not just the first year.