text/xsl
  or
  text/xml

text/xsl has never been registered (although it was used in some
examples in various documents, and it works in IE)

following the new house style for xml releated mime types it's _supposed_
to be text/xslt+xml but

text/xml

is also correct (as xslt is XML) and has the benefit of working in
IE Mozilla and netscape, so I'd use text/xml.

--
Upcoming hands-on in-depth XSLT/XPath and/or XSL-FO:
-                             North America:  Feb 3 - Feb 7,2003

G. Ken Holman               mailto:gkholman@xxxxxxxxxxxxxxxxxxxx
Crane Softwrights Ltd.        http://www.CraneSoftwrights.com/s/
Box 266, Kars, Ontario CANADA K0A-2E0  +1(613)489-0999 (F:-0995)
ISBN 0-13-065196-6                     Definitive XSLT and XPath
ISBN 0-13-140374-5                             Definitive XSL-FO
ISBN 1-894049-08-X Practical Transformation Using XSLT and XPath
ISBN 1-894049-10-1             Practical Formatting Using XSL-FO
Next conference training:                    2002-12-08,03-03,06