XML is well regarded in the enterprise and languages like JAVA, C#, and VB.NET handle is spectacularly as an exchange format.
I think it's bad reputation comes from anyone not using an enterprise language because the support just isn't there.
I recall working with a partner who we were doing an identity federation with. Our system was using WS-Trust which is a SOAP/XML protocol. It wasn't ideal but everyone seemed to support it ok. These guys were cutting edge though and used Ruby on Rails.
No support for the protocol wasn't a huge deal, just means you have to craft your XML for your SOAP calls yourself. But at the time we were doing this, RoR didn't have SOAP or XML libraries. They had to write everything from the ground up. It sucked for me and I was just fielding rudimentary questions, I can't imagine how painful it must have been for them.
> I think it's bad reputation comes from anyone not using an enterprise language because the support just isn't there.
On the contrary, I think that XML's bad reputation comes from the fact that it is so incredibly verbose.
Also, the whole child/attribute dichotomy is a huge, huge mistake. I've been recently dealing with the XDG Menu Specification, and it contains a child/attribute design failure, one which would have been far less likely in a less-arcane format.
XML is not bad at making markup languages (and indeed, in those languages attributes make sense); it is poor at making data-transfer languages.
JSON has become popular because a lot of bad programmers saw nothing wrong with calling eval on untrusted input (before JSON.parse was available). It's still more verbose than a data transfer format should be, and people default to using unordered hashes instead of ordered key-value pairs, so it's not ideal.
The best human-readable data transfer format is probably canonical S-expressions; the best binary format would probably be ASN.1, were it not so incredibly arcane. As it is, maybe protobufs are a good binary compromise?
XML is actually IMO not that bad at human readability, it's pretty good. It's terrible at human writability. Conversely S-exps are lovely to work with.