Рабочий код для vBulletin + vBseo :

define("LINKFEED_USER", "хэш код");
require_once($_SERVER["DOCUMENT_ROOT"]."/".LINKFEED_USER."/linkfeed.php");
$o["request_uri"] = $_GET["uri"];
$linkfeed = new LinkfeedClient($o);
unset($o);
$show["linkfeed"] = $linkfeed->return_links();