This is a POC idea to hook into when content node is Saved or Saved & Published do a $http Get/Post to perform some action such as auto create media folder. Then once successful show a notification with notificationService. This is a POC way to try and get around the current lack of firing a notification from an eventHandler like V6 style.

umbracoNotification.js

//Get the same base module that Umbraco uses
var app = angular.module("umbraco");

//When the module runs/excutes...
app.run(["$rootScope", "notificationsService", "eventsService", function ($rootScope, notificationsService, eventsService) {
    
    //Let's listen for any time formSubmitting
    eventsService.on("formSubmitting", function (e, args) {
        console.log("e", e);
        console.log("args", args);

        //Sad panda :(
        //This event 'formSubmitting' from formHelper.service.js only fires on the relative scope
        //And not the rootScope so have no easy way to listen in for this
        //Need another smart way?!

        //Psudeo code
            //Check for the type of docType that is being saved
            //If type == "magic"
            //Then do $http post or own service/resource with promise
                //Do some funky event stuff - create an auto media folder
            //If success promise
                //Show notificationwith notificationService.add() using JSON response from API $http

    });

    //Let's listen for any time formSubmitted
    eventsService.on("formSubmitted", function (e, args) {
        console.log("e", e);
        console.log("args", args);
    });

    //Let's listen for any time app.ready this is an event on the rootScope that is emitted
    //So this works just lovely
    eventsService.on("app.ready", function (e, args) {
        console.log("e", e);
        console.log("args", args);

        notificationsService.success("Warren", "says hello");
    });

}]); 

If anyone reads or follows this thread.
Recommend you vote up the issue here on the Umbraco Core Team Issue Tracker please
http://issues.umbraco.org/issue/U4-5927