Separating Comments, Pingbacks, Tweetbacks

I’m trying to separate the three types (using Yoast’s Tweetback plugin for the third type) but after separating out the loop, my pingbacks and appearing as reg comments and under the pingback section. see here:

http://www.wicked-pr.com/blog/social-media/seesmic-desktop-twitter-client-improves-twhirl-replaces-tweetdeck-731.html

Here is my comment loop:

<?php if ( have_comments() ) : ?>

<?php if ( !empty($comments_by_type['comment']) ) : ?>
	<a class="anchorFix" name="comments"></a>
	<ul class="commentlist" id="singlecomments">
	<?php wp_list_comments(array('type=comment', 'avatar_size'=>48, 'reply_text'=>'Reply to This Comment')); ?>
	</ul>
	<?php endif; ?>

<!-- show the tweetbacks -->	

	<?php if ( ! empty($comments_by_type['tweetback']) ) : ?>
		<a class="anchorFix" name="comments"></a>
		 <h3 id="pings">Tweetbacks</h3>
		  <ul class="commentlist" id="singlecomments">
		  <?php wp_list_comments('type=tweetback'); ?>
		  </ul>
		<?php endif; ?>

<!-- show the trackbacks/pingback -->

	<?php if ( ! empty($comments_by_type['pings']) ) : ?>
		<a class="anchorFix" name="comments"></a>
	  <h3 id="pings">Links to this Article</h3>
	  <ul class="commentlist" id="singlecomments">
	  <?php wp_list_comments('type=pings'); ?>
	  </ul>
	<?php endif; ?>

Not really sure what is happening or why. Thoughts?