Changing Wordpress "Posts" menu name in admin to ("Articles") or..

// hook the translation filters

add_filter('gettext','change_post_to_article');
add_filter('ngettext','change_post_to_article');

function change_post_to_article( $translated ) {
$translated = str_ireplace('Post','Article',$translated );// ireplace is PHP5 only
return $translated;
}