I have a counterexample - CMU's 15-112 bans laptops. The professor for it for the previous 8 years, David Kosbie, is one of the most highly regarded professors in the university.
His primary rationale for it is the "externalized cost" effect described in the article, which I can attest is quite true in my experience teaching.
When you look out at a sea of faces, you can see where the laptops are because of the reactions of people around them -- eyes keep flicking involuntarily to the interesting stuff happening on the screen, and then they peel themselves back to the lecture. It amounts to a long sequence of micro-distractions that have a pretty pronounced effect on learning. Humans are very attuned to things like motion, flickering, and changes in their field of view, and those are very present when browsing the web or reading facebook on your laptop in class. Second, laptop screens are backlit, which means that they may be the brightest object in someone's field of view in the class.
Zoning out on a kindle or printed newspaper has much less of an effect on the people around you. I don't care if someone ignores my class -- that's their choice. I used to not ban laptops, but I've become convinced that it's worth it for the other students.
Also, think about the numbers. It's very possible to have a lecture that's very engaging for about 95% of the class (which is a pretty impressive rate all-told). But the remaining 5% have about 10 students each in a field behind them that can see their laptop screen, so a very small number of students goofing off on laptops can have a disproportionate effect on the class.