jQuery AttributeObserver allow developer to bind handler to listen to HTML element's attribute changes.
$('#el').AttributeObserver(attr || callback, callback, [delay]);
//Or in the real word:
$('title').AttributeObserver('text', function(oldValue, newValue){
alert(['Page title changed from ',oldValue,' to ',newValue].join(''));
}, 1000);
//This only works with iFrame on the same domain
$('iframe').AttributeObserver('src', function(oldValue, newValue){
alert(['iFrame src changed from ',oldValue,' to ',newValue].join(''));
}, 1000);