public function getVideoDeveloperTags()
    {
        $developerTags = null;
        $this->ensureMediaGroupIsNotNull();

        $categoryArray = $this->getMediaGroup()->getCategory();
        if ($categoryArray != null) {
            foreach ($categoryArray as $category) {
                if ($category instanceof Zend_Gdata_Media_Extension_MediaCategory) {
                    if ($category->getScheme() == self::YOUTUBE_DEVELOPER_TAGS_SCHEMA) {
                        $developerTags[] = $category->getText();
                    }
                }
            }
            return $developerTags;
        }
        return null;
    }