/**
 * Usage: if ( is_new() ) : echo 'NEW!'; endif;
 * you can check if the post was posted within 30 days.
 */
function is_new($day=30,$post=null){
	$term = $day * 24 * 60 * 60;
	$post = get_post($post);
	if ( !$post || is_wp_error( $post ) )
		return false;
	$the_time = $post->post_date;
	$time = strtotime($the_time);
	$compare_time = time() - $term;

	if($time > $compare_time){
		return true;
	}else{
		return false;
	}
}