People often miss the point on why tracking is dangerous, the two comments below included.

The point isn't if the companies behave responsibly or not. Google for example has behaved responsibly with user data, exemplary in fact and I'm sure they'll continue to do so. Yet companies like Google are and will continue to be a danger for everything you know and love.

It's not how you use the data that's problematic, although companies like Facebook should suffer for their blunders, but rather that the data exists in the first place.

Are you part of a minority? Do you have some weird sexual preference or an affair? Are you a woman or gay? Are your religious views mainstream? Have you ever traveled to an Arab country or to Israel? All of these, in the right context, can put your life at risk. It's all an issue of place and timing.

You can also imagine more benign usage, like insurance companies raising their rates or banks calculating your credit score based on where you travel or your movie preferences. Heck, that's already happening.

Yes, many companies can behave responsibly. They can do so today, but what happens tomorrow, or how about in 10 years from now? What happens when those companies are being bought by bigger, less responsible ones. It happened before and it will keep happening ;-)

Of course not, but the responsible part is what’s missing. Advertisers aren’t just showing you a product, they are trying to convince you to do what they want and they’re more than willing to exploit psychology and circumstances to get you to do it. Sometimes what they want you to do is good for you too, often it is not.

> Am I the only one who wouldn't mind a responsible way for people to target me with things I don't know about which I might be interested in?

Targeting is about maximizing profits for the advertisers, it's not about maximizing value to you. If they can use targeting to take value from you in order to give it to themselves, they will. For instance, you could be bombarded with targeted ads for product A when you'd really be happier with product B. You can contrive scenarios where ad targeting is a win-win, but those scenarios are misleading because they go against the underlying incentives.

I wouldn't mind a neutral, personalized product recommendation engine, but that's not what ad targeting is.

Information not vetted by the user is often pretty inaccurate even with the best of intentions. If the user is allowed to vet it obviously it wont contain anything bad about the user including info people may ultimately desire to have.

All the information collected in service of figuring out what to advertise to you will ultimately be used for all sorts of things many of which could be to your disadvantage.

In the end you wont even know why you were denied that car loan, that job, that place to live, why you weren't deemed credible by the cops or why you were sentenced to the maximum instead of offered probation. The oracle just told the car company, the employer, the landlord, the cops, and the prosecutor what to do at different junctures based decisions that not even the people running the computer can fully explain.

Buys is the most suspect word in that. Seems more likely the kind of government that would do that is more the type to seize the company. I'm skeptical, like you, that this would end positively.

There are things which have not happened which are yet possible.