I have a hard time agreeing with this. In my experience people's single most interesting thing to talk about is themselves. Once you notice that, you see it everywhere. It's such a lure, it's almost irresistible. I've made it a habit to ask them a couple of open questions and then just let them have at it. In a few situations folks lost business with me simply because they were too preoccupied with talking about themselves to simply ask "so... how about you? what do you do?"

It follows that whenever someone has an obsession, it comes up naturally while they talk about themselves.