I've been getting my head wrapped around Ember all week, and the biggest problem I kept coming back to is that I couldn't figure out how to accept errors from the server and then route to login when appropriate in a general way. Ember really wants you to only change route from within a Route, and it does not make it easy to get the current Route from elsewhere. This appears to be because if something happens to screw with routing at the wrong time, it's a Badness, so we have to work from within those restrictions.
Long story short, I tried out ember-data and ember-auth and found both a bit too alpha/beta for my tastes at the moment. I'm sure they'll be awesome in the long run, but for now there are enough frustrating quirks and annoyances with what I was trying to do that I decided to roll my own. An excellent writeup by Robin Ward on using ember without ember-data that helped me make that decision.
With this app structure in place, any Route that u