I was told MS did not want to upgrade, because they have a 20 year support policy, and they were not sure it would have enough users to justify the expense. They were trying to correct their old image of not fixing bugs; one way was to keep versions stable. (30 years ago or so, I rang up Microsoft to complain about a bug, and they told me they do not fix bugs, because people would buy their software regardless of whether it had bugs or not: so no business justification to fix anything. Me coming from having dealt with HP and engineering sofware developers, it was so shocking to hear this from their phone support!)
My suspicion is that a lot of vendors got scared off as the run of big bad bogus technologies was launched and sucked all development budget: XSD, WS-* etc. The honeymoon was over. Then, along came JSON, which also needed to be supported and is better for some kinds of data (shame about the incompatabity). (Furthermore, because all the different environments have multiple implementations, including some like one of MS' that strips out text nodes that are only whitespace AARRGH, it was quite difficult for developers: in fact, even now there are some gotchas with factories for XML/XSD in Java on different webservers.)
Regards
Rick
