Hi Ross,
I used

function is_sf_form(){
	global $sf_form_data;
	global $wp_query;
	$search_query = $wp_query->query;
	return $sf_form_data->is_valid_form() && !empty($search_query);
}

for create is_sf_form function in my header file for showing a tag just in my search result!
after update to 2.0.1 this code not work!
I changed $sf_form_data to $searchandfilter but not work