Change Genesis default trackback format

functions.php

<?php

add_filter( 'genesis_ping_list_args', 'child_ping_list_args' );
/**
 * Take the existing arguments, and amend one that specifies a custom callback.
 * 
 * Tap into the list of arguments applied at genesis/lib/functions/comments.php.
 * 
 * @see child_list_pings() Callback for displaying trackbacks.
 *
 * @author Gary Jones
 * @link   http://code.garyjones.co.uk/change-trackback-format/
 * 
 * @param array $args Existing ping list arguments.
 *
 * @return array Amended ping list arguments.
 */
function child_ping_list_args( $args ) {
	
	$custom_args = array( 'callback' => 'child_list_pings' );

	return array_merge( $args, $custom_args );
	
}

/**
 * Echo the appearance of a single trackback.
 * 
 * Code below strips away most details about the ping, and just leaves a link to
 * the source of the ping, with the source title as the displayed text. 
 * 
 * @author Gary Jones
 * @link   http://code.garyjones.co.uk/change-trackback-format/
 * 
 * @param object  $comment Comment object.
 * @param array   $args    Comment arguments.
 * @param integer $depth   Current comment nested depth.
 */
function child_list_pings( $comment, $args, $depth ) {

	$GLOBALS['comment'] = $comment;
	?>
	<li <?php comment_class(); ?> id="li-comment-<?php comment_ID() ?>">
		<div id="comment-<?php comment_ID(); ?>">
			<div class="comment-author vcard">
				<?php echo get_avatar( $comment, $size = '48', $default = '<path_to_url>' ); ?>
				<?php printf( __( '<cite class="fn">%s</cite>' ), get_comment_author_link() ) ?>
			</div>
		</div>
	</li>
	<?php

}