This hook allows the Subscribe2 form output to be dynamically altered to suit the needs of an individual site but applies only to the AJAX popup form.
function my_s2_ajax_form($form) { // To remove the 'Your Email:' prompt text from the form $form = str_replace('Your email:', '', $form); return $form;}add_filter('s2_ajax_form', 'my_s2_ajax_form');