As somebody who has built actual applications with both Ember and Angular, I think this article totally hits the nail right on the head.

Though, in regards to the "Angular is backed by Google" comment, while they don't actually "back Ember" in the same way Google "backs Angular", it seems that a ton of large companies are also invested in Ember (http://emberjs.com/ember-users/)!

And, I know the Ember folks are really proud of the community they've built as well. I theorize that Ember's lack of a single corporate backer is what has enabled its incredible community to flourish.