Why use a Windows Phone app when there's a perfectly capable mobile website? That's a question we answered in our review of Amazon Mobile this summer:
Amazon's app for Microsoft's mobile platform does deliver the same functionality as the mobile site, but does it better. Not only does it deliver it in a Metro-styled environment that will feel comfortable to users, it also takes advantage of the opportunities available to a native application, the main one being the barcode scanner.
The idea here is that if you find something you want while out and about, you can scan the barcode with your smartphone's camera, and the Amazon Mobile application will find the item in the catalogue, and let you order it there from your phone, rather than from the store you're browsing in. A little cheeky, but hey, it's a dog eat dog world out there, and Amazon wants every advantage they can get.
The bottom line is that you are either an Amazon freak (like me) or this app is not going to offer you a huge benefit over the occasional mobile visit to the site... but if Amazon is a major retailer in your life, this app is strongly recommended.
You can update your copy from the Marketplace or through the AAWP App Directory.