It will be very nice if ED will allow system notification (not just email notification) for news in subscribed category (for example New discussion).
One thing is when you go to email and see email notification for subscribed category, it is not necessary that you will go to ED immediately. So you can later forgot when you go to ED and you can miss news...
On the other hand if there will be system notification you will always be reminded when you come to ED until you dont see them... the same as in ES.