Amazon needs to integrate with AllConsuming.
But the AllConsuming API doesn’t do PUT, and the Amazon webservices don’t permit modification of the wishlist.
The desired feature is the addition of an item to “my collection,” and the removal of an item from “my wishlist.” Now, Amazon could implement this as a new feature of their service, so that I can maintain a copy of my catalog there, or the LazyWeb could tie the two data sets together.