Simon Fell has commented twice on this WSDL discussion, saying that he has no problem with WSDL the concept, but has lots of issues with WSDL the reality.  I respect this constructive criticism.  He seems to like this article, but from his site I found another article that I like better.  In any case, few people have worked harder than Simon Fell on making interoperability work, including two patches to Apache SOAP 2.2.