List of post categories
<?php
$cats = array();
foreach(wp_get_post_categories($post->ID) as $c)
{
$cat = get_category($c);
array_push($cats,$cat->name);
}
if(sizeOf($cats)>0)
{
$post_categories = implode(',',$cats);
} else {
$post_categories = "Not Assigned";
}
echo "Categories for this post are: " . $post_categories;
?>