The official guide was decent. It does an amazing job covering everything it attempts to cover. My problem is with the things it doesn't cover. Specifically, I'd like it to be more practical by answering the question: "How do I get started immediately?" That means going into more detail about things like Ember Data, the ember-rails gem and other language/framework-specific details, etc.
Personally, I'd love to see an up-to-date tutorial for setting up a very simple Ember app with Rails or whatever. I find guides like that to be the most effective at getting people up to speed with the necessary basics.
[1] http://reefpoints.dockyard.com/ember/2013/01/07/building-an-...
From this point forward, master is committed to having all the examples in the PeepCode working until 1.0. It's been a long and wild ride mck, but the turbulence has stepped down a notch for sure.