The issue with XML is that it was mostly pushed upon developers without any deeper understanding.
So there's a ton of utterly crap XML applications out there with no rhyme or reason, and these crap XML enterprise apps are most developer's understanding of "real world XML". Similar to how terrible C++ code being all over the place is making people hate C++ the language.
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XML can be used very well however: its use in Jabber / XMPP is clear and concise. XML Namespaces are needed due to the extensions of XMPP, and various programs can interact with the protocol. Specifications are clear, the ability to "stream" data is proven, different parser strategies have been implemented. Its clear that XML in this instance works, and works pretty well.