Well my reasoning is because angular have a so called model. It's scope.
Angular doesn't need a model, it's a MV whatever. Where as ember is MVC. The framework is MVC and it's M is not complete at all. So judging from an overall framework ember is not complete in that respect where as Angular is.
Like come on, 1.0 and hey our M in our MVC framework is incomplete. Um... that's shouldn't even be 1.0. 1.0 to them is the api is going to be stable but not the emberdata, the model. Really?