$table = JTable::getInstance('Content', 'JTable', array());
$data = array(
    'title' => $my_title,
    'introtext' => $my_introtext,
    ....
    'metadata' => array(
          ...,
         'tags' => $list_of_tag[id],
          ...,
       ),
  );
$table->bind($data);
$table->check();
$table->store();