XML attributes have always bugged me. When I first learned XML I immediately disliked attributes but I was not able to articulate why I did not like them, it was just a feeling. I think I have finally figured out what exactly I dislike about attributes.
I was searching for some best practices in XML design, in an attempt to convince some people I work with that attributes are evil, and I came across Refactoring XML: The Attribute Question. It, rightly, points out that XML attributes are just syntactic sugar. Anything you can express with an attribute you can also express with an element, but not vise-versa, so strictly speaking you do not need attributes. In general, I am all for syntactic sugar, at least the sort that just removes finger-typing by making common choices for you. XML attributes, however, have different semantics than elements, for which they are syntactic sugar. The difference in semantics is a bad smell and has led to endless debates about when and why attributes should and should not be used.
XML would be a lot nicer if attributes were just a short cut for writing an element with simple content. In my perfect world
would be exactly equivalent to
<person> <name>Fred</name> </person>
Unfortunately, we are stuck with XML as it stands today, for a while anyway.