Normally I couldn't care less about ecommercial megasite redesigns, but Amazon has led quite a few innovations in the past, and I think is worth paying attention to (I have seen the site used as an case study in several usability & design books). Anyway, the page layout has changed very significantly - there is a brief summary of the changes available. My first impressions - the 'chrome' and navigation area has been cut down very significantly, and the content area expanded to take up almost the whole page - to counter this the remaining chrome/navigation has been made much richer, with lots of dropdowns (only through 2 levels). The site still fluid layout (i.e. full width), which I like. The underlying code is still full of ugly nested tables and transparent pixel gifs however. Significantly, search is now much much more prominent, taking almost half of the entire header space!