Magento: Sort latest product by ‘created date’

Use following code to sort/order product by created date
$todayDate  = Mage::app()->getLocale()->date()->toString(Varien_Date::DATETIME_INTERNAL_FORMAT);
$collection = Mage::getModel('catalog/product')
              ->getCollection()
              ->addAttributeToFilter('news_from_date', array('date' => true, 'to' => $todayDate))
              ->addAttributeToFilter('news_to_date', array('or'=> array(
                        0 => array('date' => true, 'from' => $todayDate),
                        1 => array('is' => new Zend_Db_Expr('null')))
                    ), 'left')
              ->addAttributeToSort('news_from_date', 'desc')
              ->addAttributeToSort('created_at', 'desc');