RE: Why is there little usage of XML on the "visible Web"?

“In 1665, the http://en.wikipedia.org/wiki/Royal_Society - formed to foster the growth of scientific knowledge – published the first issue of its http://en.wikipedia.org/wiki/Philosophical_Transactions.  It was a seminal moment in the history of science, because of the journal’s fierce commitment to the idea that all new discoveries should be disseminated as widely and freely as possible.  http://en.wikipedia.org/wiki/Henry_Oldenburg, the first secretary of the Royal Society and the editor of the Transactions, pioneered the idea that secrecy was inimical to scientific progress, and convinced scientists that they should give up their sole ownership of their ideas in exchange for the recognition they would receive as the creator or discoverer of those ideas.  What Oldenburg grasped was the peculiar character of knowledge, which does not, unlike other commodities, get used up as it is consumed and which can be therefore spread widely without losing its value.  If anything, in fact, the more a piece of knowledge becomes available, the more valuable it potentially becomes, because of the wider array of possible uses for it.”