The W3C XInclude working group has moved the XInclude specification back to last Call working draft to address a couple of concerns that arose during the candidate recommendation. The three major changes are:
xpointer attribute. For example, instead of writing <xinclude:include href="http://www.cafeconleche.org/#today"/> you must now write <xinclude:include href="http://www.cafeconleche.org/" xpointer="today"/>accept, accept-charset, and accept-language
attributes used to perform content negotiation with web servers.
http://www.w3.org/2003/XInclude instead of
http://www.w3.org/2001/XInclude
In my opinion this draft is a step backwards. The xpointer attribute is a really ugly kludge to work around the failure of the XLink working group to define a fragment identifier syntax for XML.
The accept attributes are underspecified, and open up some potential security holes.