I've been playing with ember also. It gets better. I'm trying to look to where ember will be vs. where it is now. The documentation leaves a lot to be desired. But they are working on it. Here is the todo gist that peter posted today on irc: https://gist.github.com/1856842#comments
I've also jumped on the Ember bandwagon and can't recommend it highly enough. The babushka design-philosophy provides huge code-leverage. Take 500 lines written against another framework, chances are Ember can do it in 250.
Just wanted to mention I'm new to ember and probably got some stuff wrong. Please help out with constructive criticism in the post's comments.
Thanks! xoxo @ngauthier