No, POST is typically for submitting data to some other "resource" for processing, while PUT is for storing data to a specific URL.
HTTP/1.1 RFC: "The fundamental difference between the POST and PUT requests is reflected in the different meaning of the Request-URI. The URI in a POST request identifies the resource that will handle the enclosed entity. That resource might be a data-accepting process, a gateway to some other protocol, or a separate entity that accepts annotations. In contrast, the URI in a PUT request identifies the entity enclosed with the request -- the user agent knows what URI is intended and the server MUST NOT attempt to apply the request to some other resource."
And from S3 documentation: "Objects are stored using the HTTP PUT method."
S3 and similar file storage services map particularly well to GET, PUT, and DELETE.
