This article seems to miss the point of RDF. I'm not sure why it's so hard to understand that "RDF provides a very natural base for the expression and interchange of such data". Making statements, pointing at name spaces all these things are not magic or even AI. But in one paragraph we go from "we want to tag pages with, say, the last name of the people who created them, is the attribute labeled "lastname", "last_name", "name_last", "surname" or "nom_dernier"" to going back to "the AI game of attempting to classify all knowledge. See Cyc. See Cyc not run."". Then he says that RDF is centralized.
This is similar to the discussion going on in the RDF interest list. If you follow this it gives some nice reasoning behind why RDF and not XML/XML Schema: