Value from template

HTML

<script src="https://raw.github.com/wycats/handlebars.js/1.0.rc.2/dist/handlebars.js"></script>
<script src="https://raw.github.com/emberjs/ember.js/release-builds/ember-1.0.0-pre.4.js"></script>
<script type="text/x-handlebars">
  {{view Ember.TextField valueBinding="firstname" placeholder="First Name"}}
  <button {{action save }}>Save</button>
</script>

JavaScript

App = Ember.Application.create();
App.ApplicationController = Ember.Controller.extend({
    save: function(){
      alert(this.get("firstname"));
    }
});