[TFEX]

Go to plugin manager, find "Product: Today's Top Poster's"
Edit "Today's Top Posters" plugin

Replace entire PHP code with this:

if ($show['todays_top_poster']) {
  $todays_top_posters = '';
  $limit = $vbulletin->options['todays_top_posters_limit'];
  $exclude_usergroups = $vbulletin->options['todays_top_posters_usergroups'];
  $exclude_users = $vbulletin->options['todays_top_posters_users'];
  $exclude_forums = $vbulletin->options['todays_top_posters_exclude_private_forums'];
  if ($vbulletin->options['24_hours_top_posters']) {
    $top_posters_title = $vbphrase['24_hours_top_posters'];
    $dateline = TIMENOW - 86400;
  } else {
    $top_posters_title = $vbphrase['todays_top_posters']; 
    $currenttime  = date('YmdHis',TIMENOW - intval($vbulletin->options['hourdiff']));  
    $dateline = TIMENOW - (substr($currenttime, 8, 2) * 3600 + substr($currenttime, 10, 2) * 60 + substr($currenttime, 12, 2));  
  }
  unset ($todays_top_posters);
  $top_posters = $vbulletin->db->query_read_slave(" 
    SELECT COUNT(post.dateline) AS postcount, post.userid, user.userid, post.threadid, thread.threadid,
    user.username, user.lastpost, user.lastpostid, user.posts, user.usergroupid, thread.forumid,
    IF(displaygroupid=0, usergroupid, displaygroupid) AS displaygroupid 
    FROM " . TABLE_PREFIX . "post AS post 
    LEFT JOIN " . TABLE_PREFIX . "user AS user ON (post.userid = user.userid) 
    RIGHT JOIN " . TABLE_PREFIX . "thread AS thread ON (post.threadid = thread.threadid) 
    " . iif(!empty($exclude_usergroups), "AND user.usergroupid NOT IN ($exclude_usergroups)") . " 
    " . iif(!empty($exclude_users), "AND user.userid NOT IN ($exclude_users)") . " 
    " . iif(!empty($exclude_forums), "AND thread.forumid NOT IN($exclude_forums)") . " 
    WHERE post.dateline > $dateline AND user.posts != '0' 
    GROUP BY post.userid  
    ORDER BY postcount DESC
    LIMIT 0, $limit"); 

  while($top_poster = $db->fetch_array($top_posters)){ 
    $top_poster[musername] = fetch_musername($top_poster); 
    $show['comma_leader'] = ($todays_top_posters != ''); 
    eval('$todays_top_posters .= "' . fetch_template('todays_top_poster_bit') . '";'); 
  } 
  eval ('$template_hook[forumhome_wgo_pos2] .= "' . fetch_template ('todays_top_poster') . '";'); 
  $db->free_result($top_posters); 
}

Your "exclude forums" field in "vbulletin options -> Today's Top Poster" will now function properly.