change content with jquery?

[buzzykerbox]

Hi i'm doing a project for college using jquery, i'd like to dynamically update a section when a link button is clicked
without reloading the page, the content fades out and the new content fades in, but when i click on a link the content fades out but the new content doesn't fade in, any suggestions, is there a better way of doing this???

$(function() {

var newHash      = "",
    $mainContent = $("#main-content"),
    $pageWrap    = $("#page-wrap"),
    baseHeight   = 0,
    $el;

$pageWrap.height($pageWrap.height());
baseHeight = $pageWrap.height() -     $mainContent.height();    

$('#list_nav li a').click(function() {
    window.location.hash = $(this).attr("href");
    return false;
});

    $(window).bind('hashchange', function(){

    newHash = window.location.hash.substring(1);

    if (newHash) {
        $mainContent
            .find("#guts")
            .fadeOut(500, function() {
                $mainContent.hide().load(newHash + " #guts", function() {
                    $mainContent.fadeIn(500, function() {
                        $pageWrap.animate({
                            height: baseHeight + $mainContent.height() + "px"
                        });
                    });
                    $("nav a").removeClass("current");
                    $("nav a[href='"+newHash+"']").addClass("current");
                });
            });
    };

});

$(window).trigger('hashchange');

});