myroute.js

var MyRoute = Ember.Route.extend({
  model: function() {
    // this will resolve
    return Ember.$.ajax().then(function(data) {
      // then this will resolve
      return Ember.RSVP.Promise.all([
        Ember.$.ajax({url: data.item1url}),
        Ember.$.ajax({url: data.item2url})
      ]).then(function(items) {
        // and this will be your model in the controller
        return {
          data: data,
          items: items
        }
      });
    })
  }
})