One of the points of the article is how people like their coffee at 140 deg F (60 deg C). I would love to know how he arrived at the stats for that since people who like drinking coffee like it at varying temperatures, from "iced" coffee to hot which can be over 80 deg C (which I prefer by the way). It really depends on the drinkers preference. To me 60 deg C is insipid, still that is a personal opinion.
To me the very idea of paying US$40 for a cup that will keep coffee at an "insipid" temperature is not appealing. In addition to that I do like tea as well and for the so called tea connoisseur (there are coffee ones as well) the temperature of the beverage is very important, which in the case of Green tea is between 70 and 80 deg C. For black tea the temperature is normally over 80 deg C.
Usually I find a normal thermal cup/mug will keep the temperature of the beverage for a longer time than a standard ceramic cup/mug although you can buy dual walled ceramic cups/mugs for much less than US$40.00 and they do hold the temperature of the beverage for a reasonable time, of course you do have to be careful you don't burn your self. A bit of common sense applies here, however it is unfortunate that a few people don't take responsibility for their actions usually claiming that the cup/mug did not come with a warning stating that the contents of this could be hot enough to burn you :). Still I suppose 60 deg C (140 deg F) is not really going to burn people.