5 years later we finally have a better solution. Use MutationObserver!

In short:

new MutationObserver(function(mutations) {

    console.log(mutations[0].target.nodeValue);

}).observe(

    document.querySelector('title'),

    { subtree: true, characterData: true, childList: true }

);

With comments:

// select the target node

var target = document.querySelector('title');



// create an observer instance

var observer = new MutationObserver(function(mutations) {

    // We need only first event and only new value of the title

    console.log(mutations[0].target.nodeValue);

});



// configuration of the observer:

var config = { subtree: true, characterData: true, childList: true };



// pass in the target node, as well as the observer options

observer.observe(target, config);

Also Mutation Observer has awesome browser support: