What function is the Rails component serving? Is it just a REST interface or is it also acting as a separate HTML interface?
The hope is to make it awesome for other JS frameworks too, but we mostly build Ember apps ourself, so you start with what you know...
You haven't seen the full power of AMS yet, but I have some exciting things planned. :)
Also you should look into active model serializers for integrating rails with ember. I think it's yehuda Katz' preferred method for Jason serialization from rails to ember.
That is true. AMS + Ember-data = 馃憤 (I'm now maintaining AMS, but Yehuda and Jose Valim originally wrote it for this purpose.)