You are not building any HTML element, try to enclose your text in a div
instead.
Code:
var $fulaDate = $('<div>'+d.getFullYear() + "-" + d.getMonth() + "-" + d.getDate() + "T" + d.getHours() + ":" + d.getMinutes() + ":" + d.getSeconds()+'</div>').appendTo(div);
Demo: http://jsfiddle.net/9jsjw/
UPDATE
If you want to display the month name use an array of month and get its description using the month index.
Code:
var monthNames = ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'];
var $fulaDate = $('<div>'+d.getFullYear() + "-" + monthNames[d.getMonth()] + "-" + d.getDate() + "T" + d.getHours() + ":" + d.getMinutes() + ":" + d.getSeconds()+'</div>').appendTo(div);