Highlight new or unread items with <span class="badge">
For easy implementation, labels and badges will simply collapse (via CSS's :empty selector) when no content exists within.
<span class="badge">1</span><a href="#">Inbox <span class="badge">31</span></a><ul class="nav nav-pills nav-stacked">
<li class="active"><a href="#">Messages <span class="badge pull-right">13</span></a></li>
<li><a href="#">News <span class="badge pull-right">2</span></a></li>
</ul>