Index: wp-includes/pluggable.php
===================================================================
--- wp-includes/pluggable.php	(revision 25014)
+++ wp-includes/pluggable.php	(working copy)
@@ -1748,3 +1748,18 @@
 }
 endif;
 
+/**
+ * Determines if the User Operating System is Mac OS X or not
+ *
+ * Uses User Agent sniffing
+ * @since  3.6
+ * @return  boolean Returns true if the operating system is a Mac and false otherwise
+ */
+if( !function_exists( 'is_osx' ) ) :
+function is_osx() {
+	if( strpos( $_SERVER['HTTP_USER_AGENT'], 'Macintosh; Intel Mac OS X' ) !== false )
+		return true;
+	
+	return false;
+}
+endif;
Index: wp-admin/options-permalink.php
===================================================================
--- wp-admin/options-permalink.php	(revision 25014)
+++ wp-admin/options-permalink.php	(working copy)
@@ -64,6 +64,13 @@
 	jQuery('#permalink_structure').focus(function() {
 		jQuery("#custom_selection").attr('checked', 'checked');
 	});
+	jQuery('#rules').on('focus',function(ev){
+		jQuery(this).select();
+		jQuery(this).on('mouseup', function(ev){
+			jQuery(this).unbind('mouseup');
+			return false;
+		});
+	});
 });
 //]]>
 </script>
@@ -271,7 +278,7 @@
 	<?php endif; ?>
 <?php else :
 	if ( $permalink_structure && ! $usingpi && ! $writable ) : ?>
-<p><?php _e('If your <code>.htaccess</code> file were <a href="http://codex.wordpress.org/Changing_File_Permissions">writable</a>, we could do this automatically, but it isn&#8217;t so these are the mod_rewrite rules you should have in your <code>.htaccess</code> file. Click in the field and press <kbd>CTRL + a</kbd> to select all.') ?></p>
+<p><?php _e( sprintf( 'If your <code>.htaccess</code> file were <a href="http://codex.wordpress.org/Changing_File_Permissions">writable</a>, we could do this automatically, but it isn&#8217;t so these are the mod_rewrite rules you should have in your <code>.htaccess</code> file. Click in the field <span class="hide-if-js">and press <kbd>%s + A</kbd></span> to select all.', is_osx() ? 'Command (⌘)' : 'CTRL' ) ) ?></p>
 <form action="options-permalink.php" method="post">
 <?php wp_nonce_field('update-permalink') ?>
 	<p><textarea rows="6" class="large-text readonly" name="rules" id="rules" readonly="readonly"><?php echo esc_textarea( $wp_rewrite->mod_rewrite_rules() ); ?></textarea></p>