I have read that Ember2 is attempting to remove controllers. I was even linked to this RFC https://github.com/ef4/rfcs/blob/routeable-components/active/0000-routeable-components.md. However, I have been following the tutorial, and they insist on making a Controller. Do we still need to make Controllers or is this out of date?
Controllers are still needed (and thus haven't been deprecated) for two reasons: query parameters, and because components aren't routable yet. You can follow the tutorial's use of controllers without it causing you too much grief later on.
However, if you want to pull ahead of the tutorial, you can use components instead, barring the two caveats above. There is no way around using controllers for query parameters, but you can avoid the lack of routable components using this simple hack:
Let's say you're creating a Route called Dashboard. The tutorial will tell you to create corresponding Controller and Template as well. Go ahead and do that, but delete the Controller. Create a component called dashboard-main, move the logic from the Controller to the component.js file and the Template to the component's Template. Then, in the Dashboard Template, just refer to the component:
{{dashboard-main items=model foo=foo bar=bar ...}}
Depending on what you're doing in the Route, you still may need the setupController() method (that's still the only way you can move values other than the model from the route to the template so that they can be passed to the component), and of course your controller/component implementation may have other minor changes, but that's the basic gist of it.
To be most ready for when controllers are deprecated, you should avoid them by using components instead.