<a href="http://content.fortune.com/wp-content/uploads/2012/05/capture3.jpg"><img class="alignright size-full wp-image-35517" title="Capture" src="http://content.fortune.com/wp-content/uploads/2012/05/capture3.jpg" alt="" width="401" height="252" /></a>Facebook is now public. How did the private traders do?