Your code seems ok to me. Which Ember.js and app-kit versions do you use?
I tried to replicate your issue but everything worked well. Can you please replicate my scenario and verify that it also works for you?
What I did:
$ git clone git@github.com:stefanpenner/ember-app-kit.git
$ cd ember-app-kit
$ npm install
Made these code changes (my git diff):
diff --git a/app/controllers/application.js b/app/controllers/application.js
new file mode 100644
index 0000000..9d34ee0
--- /dev/null
+++ b/app/controllers/application.js
@@ -0,0 +1,5 @@
+var ApplicationController = Em.Controller.extend({
+ title: 'hello world'
+});
+
+export default ApplicationController;
diff --git a/app/templates/application.hbs b/app/templates/application.hbs
index d08c11f..a373a71 100644
--- a/app/templates/application.hbs
+++ b/app/templates/application.hbs
@@ -1,3 +1,4 @@
<h2 id='title'>Welcome to Ember.js</h2>
+{{title}}
{{outlet}}
and finally ran
$ grunt server
and when I opened localhost:8000 everything worked fine ("hello world" was rendered). Can you please try it out?