[assassingod]

PHP Code:

$toppostersquery = $DB_site->query("
 SELECT 
   userid,
   username,
   COUNT(*) as weekpostcount
 FROM
   post
 WHERE
   dateline > (UNIX_TIMESTAMP() - 7*24*60*60)
 GROUP BY
   username,
   userid
 ORDER BY
   weekpostcount DESC
 LIMIT 5
");
while ($topposters  = $DB_site->fetch_array($toppostersquery))
{
  eval("\$toppostersbit = \"".gettemplate('topposters_7days')."\";");
} 


Then you'd use something like in the topposters_7days template:

<b>$topposters[username]</b>  -$topposters[posts]

Untested but that should do it for you