Your code shows this:
HTML Code:
<vb:if condition="$block_data['visitorcount'] > 0">
<div class="meta">
{vb:rawphrase last_x_visitors, {vb:raw block_data.visitorcount}}
</div>
<ol class="commalist">
{vb:raw block_data.visitorbits}
</ol>
</vb:if>
Whereas the default template shows this:
HTML Code:
<vb:if condition="$block_data['visitorcount'] > 0">
<div class="meta">
{vb:rawphrase last_x_visitors, {vb:raw block_data.visitorcount}}
</div>
<ol class="commalist">
<vb:each from="block_data['visitorbits']" value="row">
<li><a class="username" href="{vb:link member,{vb:raw row}}">{vb:raw row.musername}</a>{vb:raw row.invisiblemark}{vb:raw row.buddymark}{vb:raw row.comma}</li>
</vb:each>
</ol>
</vb:if>
You need to compare your template to the default template and then fix the code.