Like many other discussions (though perhaps much faster than most 8-), Simon gets to the heart of the matter;
[…] but at that level so is SOAP, its always HTTP POSTs[…]
While trying not to sound too much like a broken record, there is just one “level” here, the application layer; HTTP methods are application methods. POST is as much an application method as doSearch(). When you use HTTP/REST, you as a developer aren’t normally defining any methods, you’re just filling in the arguments to the methods that HTTP provides. That’s what “interface” in the uniform interface constraint is referring to; the API.