The IT industry has long known and exploited a host of tricks, including cookies and link tracking, but reports in mainstream media will bring this to the attention of a wider, and increasingly paranoid, population of users.
On the one hand, people should realize that Yahoo, Hotmail and Gmail and Facebook don't provide their services out of generosity and kindness: their 'free lunch' is paid for through advertising, targeted on the basis of what they know about their users.
On the other hand, as this realization dawns more completely, expect users increasingly to place a value on their privacy and ability to have control over their information. So far, users are resisting paid-for web services, but there's every indication that, in some markets, this will change.
