So I know to do this the way I'm thinking would be a pretty big thing to do but here's my thought. I sometimes don't set up alerts for things since I hate getting flooded with emails about it. My thought is if instead of sending an email it could work like Facebook where you can see a list of notifications in a dropdown say at the top of the page like how the cart is right now. A simpler option would be to have it send a message to your account's messaging area but I think the facebook thing would be easier/ better less