Do I really want to see someone exclaim "I'm well known now!" or "New username" or "Don't insult me"? How are such things worth the space they take up in the sidebar?
It's like reading facebook. Completely inane. Makes you realize that, yes, everyone you know and don't know has many thoughts each day and that, indeed, you don't really want to know what they are--or it makes you realize that if your life does indeed have time to take in such things, you need a better life.