I often forget to check my notification for posts that I have been mentioned in for 2 reasons. One being that there's nothing really flashy that stands out such as a PM would. I suggest something with a little bit of a pop to catch your attention just for a second to show there's something up there. With that being said, I really don't need to know that I have quoted someone else. I often see notifications that I have quoted someone else? That's not necessary, IMO.
So in closing, let's get something that will draw attention up there slightly more than what we currently have, but nothing that will require interaction such as a pop up box.