Susan at Chicken Spaghetti has a neat post, Bookspotting, 4th Grade.
I definitely like to see what people are reading. In fact, it's all I can do to keep myself from going up to strangers and just taking their books out of their hands so I can look at the titles.
One of my sisters has sometimes talked about going to the mall to "people watch." I really don't care about watching strangers unless they're holding a book.