Do people, in general, have too much information about themselves online?

A lot of people store important personal data online such as credit card numbers, bank account information, and histories of online purchases. All of this make it easy for advertisers to create a profile of you based on previous searches and suggest certain products for you to buy. It also affects people who are interested in health insurance. Would the insurer want to know if their client had recently been searching “symptoms of colon cancer”?

So should atvertisers’ collection of data on Web users be regulated? and Are social networking sites doing enough to protect users’ privacy?