Laptops in class - with a guest lecturer?

It is November 30th, and there is a guest speaker in my Sociology class, Views from the Third World. Most of the students are paying attention to the guest speaker and participating in a discussion about the Israel-Palestine conflict. Three students are using their laptops. One of them is sitting near the front and is clearly taking notes on the discussion. The two others sitting closer to the middle that are using laptops are browsing such websites as Facebook and Myspace and are clearly not paying attention to the guest speaker. Anyone sitting behind them would easily notice that they are not using their laptops for any sort of schoolwork, and the guest speaker and the professor should easily have noticed that these students were focusing solely on their computers, but there was no response from either.