Of Authoritative Metadata and Content-Type

I noticed this the other day:

  http://ln.hixie.ch/?start=1144794177&count=1

Ian observes

     Browsers and other user agents largely ignore the HTTP
     Content-Type header, relying on undefined sniffing heuristics to
     determine what the content of a page really is.

and provides a very useful set of test data. However, I find his
conclusion

     I think it may be time to retire the Content-Type header, putting
     to sleep the myth that it is in any way authoritative, and
     instead have well-defined content-sniffing rules for Web content.

more than a little worrisome. At the very least, it suggests that some
significant applications don't consider authoritative metadata, well,
authoritative.

                                        Be seeing you,
                                          norm

-- 
Norman.Walsh@Sun.COM / XML Standards Architect / Sun Microsystems, Inc.
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