You seem to be equating "web services" with "SOAP-based services". But the technologies you mention are not alternatives to "web services", they are alternatives to "SOAP-based web services". So the question you seem to be asking is really "What's the benefit, if any, of
SOAP over REST (and/or other HTTP/XML service approaches)?" One of the benefits are the capabilities that come with the full SOAP stack as implemented by the various WS-* standards, like WS-Security and BPEL. If a particular service implementation doesn't need those, then, indeed, the overhead of SOAP may not be justifiable.
True, UDDI has failed to take off (although, interestingly, a new version of the standard is forthcoming), since web service registries in general have not established themselves. But that's not a failure of SOAP, that just means that the market has developed in a different direction than originally anticipated. So it can just be ignored, and doesn't add any complexity to SOAP itself.
The
http://faq.javaranch.com/java/WebServicesFaq links to several articles that cover this in more detail in the "What is REST?" section.
