1) Nobody moved away from XML syntax. You can still use it if you want.
2) In most cases XML syntax is pointelss.
3) HTML5 has nothing to do with CSS, and CSS is doing fine, far from being "massive failure".
It doesn't matter whether I can use XML. What matters is that some people will use a new syntax and all the integration hassles and incompatibilities will start once again.
Why is it a good idea to invent yet another syntax that is almost the same but not quite compatible?
Looking at the ridiculous guru culture that has formed around minor obscure CSS features is very telling. When that happens to a technology I call it a massive failure.
"HTML 5 is being written in two syntaxes: html and XML. Because SGML has never been deployed in browsers and many html authoring tools, HTML 5 defines a new serialization called html, which looks a lot like the previous known SGML."
