Dare Obasanjo has an article called the XML Litmus Test to determine if XML is appropriate for certain applications. It seems to be an elaboration on a response he made to my earlier rant, although I doubt that was the entire motivation. He demonstrates an INAPPROPRIATE use of XML, which I hope really raises the ire of some of the knee-jerk “XML will cure cancer“ type people out there. :)
Although, I have to say his example is one of those esoteric things that most people will never get into anyway, and therefore not particularly relevant to the discussion. It's still a good read, and I hope it will help people make more informed decisions about when and when not to use XML.
BTW, Dare was, until very recently, part of the XML Team at Microsoft and a major XML evangelist. Thankfully SOMEONE at Microsoft is finally speaking up about when NOT to use a feature! :)