XML, or eXtended Markup Language is fairly a new buzzword in web development things. It’s just a simple text file with tags that we can define ourselves. The aim of XML is to create a “simple and re-distributable data”.
But I’ve seen many sites/companies using XML in a wrong way. Well, not so wrong. Just don’t match with XML aims. Many sites using XML as a replacement of common RDBMS. They use XML for storing the data and keep it in their harddrives.
It’s okay if it’s a new system. But spending money rebuilding the system so it can be used with XML just to be “up to date” is a kind of silly things. Just DON’T USE XML if you DON’T REALLY NEED XML.