How Private Are Sites' Membership Lists?: "Slashdot contributor Bennett Haselton has written an essay on a subtle privacy issue affecting many websites (including Slashdot!) He says 'Suppose your girlfriend called up Match.com and said, 'I think my boyfriend might be cheating on me. His e-mail address is joeblow - at - aol - dot - com. Can you tell me if he's a member?' And Match.com phone support told her, 'Why, yes, he is a member. You'd better have a talk with him.' After you had gotten over the guilt of getting caught -- I mean, the guilt of cheating -- would you not feel like Match.com had violated your privacy by telling a third party that you were a member?' Keep reading to see what he's getting at and to decide if and when it's a problem.

(Read Original Article - Via Slashdot.)