Ember 0.9.8.1 Template

HTML

<script src="https://github.com/downloads/emberjs/ember.js/ember-0.9.8.1.js"></script>
<script type="text/x-handlebars">
    
</script>

JavaScript

App = Ember.Application.create(); 

App.FooMixin = Ember.Mixin.create({
    barBazDidChange: function() {
        console.log('barBazDidChange'); // never called
    }.observes("bar.baz")
});

App.Foo = Ember.Object.extend();

App.fooObject = App.Foo.create({
    bar: Ember.Object.create({
        baz: "ember"
    })
});