Edit thread title via script

[TeamDevotion]

Why doesn't this work??

I used a lot of the code found in posting.php to come up with this, but for some reason, it does not edit my thread title. I do not receive any database errors or anything of that nature.

$editthreaddm =& datamanager_init('Thread', $vbulletin, ERRTYPE_STANDARD, 'threadpost');
		$threadid = 2369;
		$threadinfo = fetch_threadinfo($threadid);
		$editthreaddm->set_existing($threadinfo);
		
		$newtitle = $user['username'] . "'s mic check 12" . $year . " " . $make . " " . $model . " [" . $color . "]"; 
		//replace index
		$editfirstpost = $db->query_first_slave("
			SELECT *
			FROM " . TABLE_PREFIX . "post
			WHERE threadid = $threadinfo[threadid]
			ORDER BY dateline, postid
			LIMIT 1
		");
		$editfirstpost['threadtitle'] = $newtitle;
		delete_post_index($editfirstpost['postid'], $editfirstpost['title'], $editfirstpost['pagetext']);
		$forumid = 59;
		$foruminfo = fetch_forum_info($forumid);
		build_post_index($editfirstpost['postid'] , $foruminfo, 1, $editfirstpost);
		$editthreaddm->set('title', $newtitle);
		($hook = vBulletinHook::fetch_hook('threadmanage_update')) ? eval($hook) : false;
		$editthreaddm->save();