After submitting a POST form open a new window showing the result

If you want to create and submit your form from Javascript as is in your question and you want to create popup window with custom features I propose this solution (I put comments above the lines i added):

var form = document.createElement("form");
form.setAttribute("method", "post");
form.setAttribute("action", "test.jsp");

// setting form target to a window named 'formresult'
form.setAttribute("target", "formresult");

var hiddenField = document.createElement("input");              
hiddenField.setAttribute("name", "id");
hiddenField.setAttribute("value", "bob");
form.appendChild(hiddenField);
document.body.appendChild(form);

// creating the 'formresult' window with custom features prior to submitting the form
window.open('test.html', 'formresult', 'scrollbars=no,menubar=no,height=600,width=800,resizable=yes,toolbar=no,status=no');

form.submit();

Simplest working solution for flow window (tested at Chrome):

<form action='...' method=post target="result" onsubmit="window.open('','result','width=800,height=400');">
    <input name="..">
    ....
</form>

Add

<form target="_blank" ...></form>

or

form.setAttribute("target", "_blank");

to your form's definition.

var urlAction = 'whatever.php';
var data = {param1:'value1'};

var $form = $('<form target="_blank" method="POST" action="' + urlAction + '">');
$.each(data, function(k,v){
    $form.append('<input type="hidden" name="' + k + '" value="' + v + '">');
});
$form.submit();