Interesting article on the authority of data sources in which Tim O'Reilly also makes a very recognizable remark on software bugs..;-)
"Aside: That's a classic bug cascade. As my friend Andrew Singer once noted, debugging is discovering what you actually told your computer to do, rather than what you thought you told it. Unfortunately, you sometimes don't understand what you told your computer to do until some particular corner case emerges.)"
And the Web 2.0 lesson:
"But it's a real shame that it's not possible just to remove the bad data. As Lou said in one email, "the whole story seems to be such a strong illustration of the downsides of connected and linked databases (and therefore very much a Web 2.0 lesson)."