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From the Wall Street Journal
Facebook's Tracking of User Activity
Riles Privacy Advocates, Members
By VAUHINI VARA
November 21, 2007; Page D8
Some users of the Facebook Inc. Web site have been startled by a new feature that tracks their activity outside of the site and shows it to their friends -- renewing questions about the privacy implications of a growing practice of exploiting personal information in online advertising.
The social-networking service earlier this month began posting updates about users' activities on Web sites outside of Facebook and on commercial pages within Facebook -- in some cases, alongside ads from the companies behind those Web sites or pages. Facebook is posting users' photos alongside certain advertisements, another feature that has alarmed some privacy advocates and users.