] To be sure, companies have long gathered personal and
] shopping information to better market to customers, often
] with dubious results. Who hasn't received junk mail or
] telemarketing calls that seem to have no connection with
] their lives? But those initiatives are fast improving and
] accelerating as people live more of their lives tethered
] to cell phones, the Internet and the rest of the wired
] world, where trading off personal information is part of
] the price of admission.

Interesting summary (more of a catalog, really) of this trend.

Privacy Eroding, Bit by Byte (washingtonpost.com)