This question applies to WordPress, but maybe someone knows if it applies universally?
Is there a proper mime-type (type attribute) for this... ?
<link rel="pingback" type="WHICH-TYPE/HERE?" href="http://www.example.com/xmlrpc.php" />
Something tells me it may be text/xml, but I'd rather not guess if someone knows the right answer.
EDIT:
I am reading here that including a link rel pingback in your <head> is discouraged...