People who think XML is a better configuration file format are sorely mistaken and are all eating it for their initial opinion. Even the creator of Ant (the infamous Java based build tool) admitted that XML was a bad decision
. It's hard to read, error prone to write and overly complex to manipulate even for a machine. You can fill a book
with the API (let alone the specification), and using it is not pretty, even in the highest level languages.
Ini files are simplistic and obvious, both to a user and to a machine. Configuration files don't need "nesting". Nesting doesn't make parsing or accessing data any easier, either.
Of course, none of this has anything to do on whether mIRC should have XML parsing capabilities.
Writing an mIRC based parser would be easy, but probably ridiculously slow. Of course DLLs do the job just fine here, though with so much web out there, mIRC could be more helpful to socket scripts that try to integrate with web services (or scrape pages), which seems to be a common scripting task these days.
That said, XML is still a huge api, making it quite high maintenance for something to be supported directly by mIRC. It would require plenty of identifiers and plenty of API wrapping to work properly, so only time will tell if Khaled wants to take this up. In the meantime, use a DLL and don't expect this to be added to mIRC any time soon.