jetpack.statusBar.append({
    html: '<span id="jetpack-tabcount">' + jetpack.tabs.length + '</span>',
    onReady: function(widget){
        $('#jetpack-tabcount', widget).css({
          cursor: 'pointer'
        });
        var updateTabcount = function() {
          $('#jetpack-tabcount', widget).text(jetpack.tabs.length);
        };
        jetpack.tabs.onOpen(updateTabcount);
        jetpack.tabs.onClose(updateTabcount);
        $(widget).click(updateTabcount);
    }
});