bbPress

Add the topic-voices.php file to bbPress' my-plugins/ directory and activate.

It is recommended but not required to go to the Manage->Recount admin menu and recount voices.

Edit your templates as desired to display voices in your topic lists (front-page.php forum.php view.php tag.php) and on the topic.php template itself.

The two added functions are bb_get_topic_voices(); and bb_topic_voices();

For example, you can add a column like so on your front-page.php

<th><?php _e('Posts'); ?></th>
<th><?php _e('Voices'); ?></th>
<th><?php _e('Last Poster'); ?></th>


<td class="num"><?php topic_posts(); ?></td>
<td class="num"><?php bb_topic_voices(); ?></td>
<td class="num"><?php topic_last_poster(); ?></td>