Index: wp-includes/default-filters.php
===================================================================
--- wp-includes/default-filters.php	(revision 15513)
+++ wp-includes/default-filters.php	(working copy)
@@ -180,6 +180,7 @@
 
 // Actions
 add_action( 'wp_head',             'wp_enqueue_scripts',            1     );
+add_action( 'wp_head',             'profile_rel_link',              1     );
 add_action( 'wp_head',             'feed_links',                    2     );
 add_action( 'wp_head',             'feed_links_extra',              3     );
 add_action( 'wp_head',             'rsd_link'                             );
Index: wp-includes/link-template.php
===================================================================
--- wp-includes/link-template.php	(revision 15513)
+++ wp-includes/link-template.php	(working copy)
@@ -1301,6 +1301,27 @@
 }
 
 /**
+ * Get site profile relational link.
+ *
+ * @since 3.1.0
+ *
+ * @return string
+ */
+function get_profile_rel_link() {
+	$link = "<link rel='profile' href='http://gmpg.org/xfn/11' />\n";
+	return apply_filters( "profile_rel_link", $link );
+}
+
+/**
+ * Display relational link for the site profile.
+ *
+ * @since 3.1.0
+ */
+function profile_rel_link() {
+	echo get_profile_rel_link();
+}
+
+/**
  * Display previous post link that is adjacent to the current post.
  *
  * @since 1.5.0