I've been told my last posting was too long, so here's the short version.
All MIME media types for XML-based documents will get the suffix '-xml'.
The registration process will follow normal IETF procedures per RFC 2048.
Advantages: Applications that can process XML generically will be able to
request content types of */*xml and get useful results for further
processing. Tools designed to work with XML in general (XPointer, XLink,
style sheets) will be easy to use with any registered MIME type that uses XML.
Disadvantages: Er... four extra bytes in the content-type header?
Simon St.Laurent
XML: A Primer / Building XML Applications
Inside XML DTDs: Scientific and Technical
Sharing Bandwidth / Cookies
http://www.simonstl.com