I particularly enjoyed this paragraph:
"The most popular learning systems sold today â€” for instance, foreign language software like Rosetta Stone â€” cheerfully defy every one of the psychologists' warnings. With its constant feedback and easily accessible clues, Rosetta Stone brilliantly creates a sensation of progress. "Go to Amazon and look at the reviews," says Greg Keim, Rosetta Stone's CTO, when I ask him what evidence he has that people are really remembering what they learn. "That is as objective as you can get in terms of a user's sense of achievement." The sole problem here, from the psychologists' perspective, is that the user's sense of achievement is exactly what we should most distrust."