small change in php snippet

I found this code snippet on the php snippets page:

<?php
$num_nodes = 7;
$result = db_query_range(db_rewrite_sql('SELECT n.nid, n.title
FROM {node} n
WHERE n.status = 1 ORDER BY n.changed DESC'), 0, $num_nodes);
$output = node_title_list($result);
$output .= l('More articles ...', 'tracker');
print $output;
?> 

It would be very helpful for me to know how this snippet can be extended so that it displays the category of every listed node. In addition, a post count would also be helpful. I thank you for your know-how in this matter.