Popover Bootstrap em Imagem

HTML

<link rel="stylesheet" href="http://netdna.bootstrapcdn.com/twitter-bootstrap/2.3.2/css/bootstrap-combined.min.css">
<script src="http://netdna.bootstrapcdn.com/twitter-bootstrap/2.3.2/js/bootstrap.min.js"></script>
<a id="user" title="" data-content="As minhas informações inseridas aqui" data-placement="right" data-toggle="popover" class="btn" href="#" data-original-title="Popover à Direita">
    <img src="http://open.spotify.com/static/images/user.png"/>
</a>

CSS

a {
    margin: 10px;
    border: 2px solid #CCC;
    padding: 5px;
    overflow: hidden;
    display: block;
}

img {
    width:100px;
    height:100px;
}

JavaScript

$('#user').popover();