FYI everyone here, this is not even sync. It's a drag and drop to upload applet :)
http://www.amazon.com/gp/help/customer/display.html?nodeId=2...
"Note: The Cloud Drive Sync application (formerly, the "Cloud Drive desktop application") is no longer available for download. If you already have the application installed on your computer, you can continue to use it. However, if you uninstall the application, you won't be able to reinstall it from the website."