<?php
$post = $wp_query->post;
if ( in_category(70) || in_category(89) || in_category(88) || in_category(103) || in_category(97) || in_category(98) || in_category(99) || in_category(100) || in_category(101)) { 
include(TEMPLATEPATH . '/single4.php');
} else if ( in_category(104) || in_category(105) || in_category(106))  { 
include(TEMPLATEPATH . '/single3.php');
} else {
include(TEMPLATEPATH . '/single2.php');
}
?>