[TiKu]

Here's another improvement:
Add a plugin called "Quote Full CMS Article", hook newreply_quote.

if (THIS_SCRIPT == 'ajax' AND $quote_post['forumid'] == $vbulletin->options['vbcmsforumid']) {
	$is_first_post = false;
	$result = $vbulletin->db->query_first("SELECT postid FROM " . TABLE_PREFIX . "post WHERE threadid=" . $quote_post['threadid'] . " ORDER BY dateline LIMIT 1");
	if($result) {
		$is_first_post = ($result['postid'] == $quote_post['postid']);
	}

	if($is_first_post) {
		$result = $vbulletin->db->query_first("
		  SELECT cms_article.pagetext, cms_article.threadid, cms_node.nodeid, cms_node.userid
		  FROM " . TABLE_PREFIX . "cms_article AS cms_article
		  INNER JOIN " . TABLE_PREFIX . "cms_node AS cms_node ON (cms_node.contentid = cms_article.contentid)
		  INNER JOIN " . TABLE_PREFIX . "cms_nodeinfo AS cms_nodeinfo ON (cms_nodeinfo.nodeid = cms_node.nodeid)
		  WHERE cms_nodeinfo.associatedthreadid = ". $quote_post['threadid']. "
		");

		if($result) {
			bootstrap_framework();
			$contenttypeid = vb_Types::instance()->getContentTypeID('vBCms_Article');
			$allow_html = vBCMS_Permissions::canUseHtml($result['nodeid'], $contenttypeid, $result['userid']);

			$bbcode_parser = new vBCms_BBCode_HTML($vbulletin, vBCms_BBCode_HTML::fetchCmsTags());
			$pagetext = $bbcode_parser->get_preview(fetch_censored_text($result['pagetext']), $vbulletin->options['default_cms_previewlength'], $allow_html);
		}
	}
}

This makes quotes of the first post of the comments thread quote the article's preview text instead of the link to the article.