The Numerati, written by Stephen Baker, is a must read. The title is an in-depth account of the market segmented world we now live in - a place where its all about the numbers and "behavioral clues" for brands, as well as governments. From NYT's review:

"Baker offers an anecdote about a firm called Umbria helping a cellphone company that's decided to charge more for Bluetooth data connections, a move that "sent bloggers into a fury." Umbria, which studies bloggers and divides them into tribes, concluded that all the spleen-venting was coming from the "power users," whereas "the fashionistas, the music lovers, the cheapskates" did not care. "With this intelligence," Baker writes, the company could placate the power users by offering them "free" service (while raising the prices on headsets) and "continue charging everyone else."

As PSFK noted about this type of number crunching: "This kind of personal information has been available to anyone who wanted it for a long time, but with the increasing amount of time that we now spend online, the details of who we are based on this activity is getting easier to extract."

On internet Big Brother? Are you out there?

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