Sto studiando le tecniche TML5 evorrei discutere su History API pushState (HTML5)

Ho letto che è possible scriverci sulla URL.
Ma ancora non ci riesco
Vorrei che il vecchio Url da

file:///media/DATA/prototypefin4/s.html

e aggiungendo foo=1&foo=2 (variable s) sulla Url con History.pushState diventa

file:///media/DATA/prototypefin4/s.html?=foo=1&foo=2

ma come?

Allego il mio piccolo progetto

<!DOCTYPE HTML>
<html>
<head>
<title>Example - History API pushState</title>
</head>
<script src="http://balupton.github.com/history.js/vendor/jquery.js"></script>
<script src="http://balupton.github.com/history.js/scripts/bundled/html4+html5/jquery.history.js"></script>
<script src="//ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script>
<script src="//ajax.googleapis.com/ajax/libs/jqueryui/1.10.2/jquery-ui.min.js"></script>
<body>

<input id = 'button1' type = 'button' value = 'history.pushState' onclick="updateHistory()"/>

<script type = 'text/javascript'>

var count ="?foo=1&foo=2";

function updateHistory()
{

History.pushState(count,null,file:///media/DATA/prototypefin4/s.html);

}

</script>

</body>
</html>