Setting the question of "more and appropriate @rel values" aside, why prefer rel="printer-friendly" over rel="print"?
I.e., if people really do want to go there, why not at least stay consistent with the HTML4/CSS2 media naming conventions?
http://www.w3.org/TR/html4/types.html#h-6.13 http://www.w3.org/TR/CSS2/media.htmlBut instead of changing the rel value away from the perfectly reasonable "alternate", why not just add @media to the link?
<link rel="alternate"
media="print"
type="text/html"
href="" href="http://www.xml.com/?print=1">http://www.xml.com/?print=1"/>
This is also where HTML5 is headed:
http://www.w3.org/html/wg/html5/#the-link
-DeWitt