Give this a shot:
<?php
/* Add WYSISYG editor to comment form. */
add_filter( \'comment_form_field_comment\', \'wpse_64243_comment_editor\' );
function wpse_64243_comment_editor( $field ) {
if (!is_single()) return $field; //only on single post pages.
global $post;
ob_start();
wp_editor( \'\', \'comment\', array(
\'textarea_rows\' => 15
) );
$editor = ob_get_contents();
ob_end_clean();
//make sure comment media is attached to parent post
$editor = str_replace( \'post_id=0\', \'post_id=\'.get_the_ID(), $editor );
return $editor;
}