Reply To: [Assigned] Views hooks for adding new search form fields

wpv_view_settings_save, it is a Views filter hook when you save a view:
incwpv-plugin.class.php Line 575:
$_POST['_wpv_settings'] = apply_filters('wpv_view_settings_save', $_POST['_wpv_settings']);
incwpv-pagination.php Line 32:
$settings = apply_filters('wpv_view_settings_save', $settings);