I have just discovered two new WordPress plugins that will help you show comment love to your commentators. The first is the Show Top Commentators Plugin.  This plugin will show the Top Commentators on your blog with a link back to their website or blog.  Upload the plugin to wp-content/plugins directory and activate it.  If you are NOT using widgets, you are finished!  If you do use widgets, you will also need to download and install the Exec-PHP plugin and activate it as well.  This plugin will place a PHP Code 1 box in your Available Widgets.  Drag the PHP Code 1 box where you would like it on your sidebar and then edit it.  Include the following code:

<?php if(function_exists('ns_show_top_commentators')) { ?>
<li>
<ul><?php ns_show_top_commentators(); ?></ul>
</li>
<?php } ?>

Name the Widget “Top Commentators” and save changes.  Finished!

The second Plugin is called Comment Relish written by Justin Shattuck. This plugin will send an email message to a commentator the first time they leave a comment. After uploading the plugin to your wp-content/plugins directory, activate the plugin. To configure the plugin, click on the Plugins tab and then choose Comment Relish. The cool thing about this plugin is that you can add the article name, your RSS Feed, the comment that was posted as well as other items to the thank you note.

NOTE:  If you have problems with Comment Relish, there is a new optimized version as well.