module_load_include('inc', 'node', 'node.pages');
$type = 'article';
$node = array(
  'uid' => $GLOBALS['user']->uid,
  'name' => isset($GLOBALS['user']->name) ? $GLOBALS['user']->name : '',
  'type' => $type,
  'language' => ''
);
$output = drupal_get_form($type . '_node_form', $node);

module_load_include('inc', 'node', 'node.pages');
$type = 'article';
$node = (object)array(
  'uid' => $GLOBALS['user']->uid,
  'name' => isset($GLOBALS['user']->name) ? $GLOBALS['user']->name : '',
  'type' => $type,
  'language' => LANGUAGE_NONE
);
$output = render(drupal_get_form($type . '_node_form', $node));

Drupal 6, Drupal 7