XPointer and XHTML

I may be missing the point here, but...

XPointer introduction says that it applies to
  "a resource of Internet media type text/xml or application/xml"

http://www.w3.org/TR/2000/CR-xptr-20000607.html#N598

XHTML is agnostic about its media type...

"...general recommended MIME labeling for XML-based applications has yet to 
be resolved."

and

"XHTML Documents " ... "may be labeled with the Internet Media Type 
"text/html"".

http://www.w3.org/TR/xhtml1/#media

So XPointer may or may not be usable with XHTML, is that correct?

This seems to be quite a severe shortcoming (assuming my interpretation is 
right). I think that the acceptance of XLink/XPointer technologies will be 
affected by how easily they can be added to those already existing.

Matthew Wilson