Yes its true "public mailing list" is not what I thought it was, it's not the mass mailing capability but rather if the CMS developer offers users to subscribe to notification by email, alas Drupal does but Joomla does not according to cmsmatrix.org and they are discussing Joomla 1.5.

Yet my take is that Joomla is more user friendly while Drupal is more powerful, not that I'm saying that Joomla is not powerful, both are quality CMS.