Phone screen with corporate recruiting in Seattle, filled out some questions regarding willingness to relocate and salary expectations via email, on-site interview at the fulfillment center in an "interview pod". This meant a handful of applicants sat in a "holding room" and then we kind of rotated between three interviewers, HR Business Partner, Operations Manager and HR Manager for the site. Took about half a day, but didn't need to go back for any additional interviews after the pod. Was called within the week with an offer. Matched my pay from previous employer and was quite generous with total comp package. The interview questions for this role were behavioral such as "tell me about a time you dealt with a difficult customer" or "tell me about a time you went above and beyond on a project".
Amazon is looking for answers to interview questions provided in STAR format, situation, task, action, results. The interviewee should answer in that format. If you mention a skill you have, you must provide a specific example. If you mention you saved a company money, you better know how much. If you don't provide this info, you will be asked for it. Intense interview but overall the best interview process I've ever seen at a company.