I've said this before, but the risks to privacy and online security of being on Facebook have never been so great as they are now. Salim Virani has penned a long and very detailed article showing how Facebook is abusing its users, and making a great deal of money out of them while giving nothing back. Here's an excerpt.
Through its labyrinth of re-definitions of words like “information”, “content” and “data”, you’re allowing Facebook to collect all kinds of information about you and expose that to advertisers. With your permission only they say, but the definition of “permission” includes using apps and who knows what else.
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They say they “anonymise” this, but in reality, it’s a simple step to de-anonymise it. A lot of the anonymous data, like what and when you posted, pictures of you, your location at a given time, is enough for a huge number of companies to tie that anonymous data back to you – and sell it on.
On top of this, they allow all the Facebook apps full access to your information - with your name and everything. And even if you never use any apps on Facebook, your friends do. When they use apps, your friends share all your information for you. There’s a whole industry behind this.
Some things DO have off buttons, but keep in mind they are temporary, and as Facebook has done in the past, it will switch them back on without letting you know. When Facebook started (and probably when you joined) it was clearly a safe place to share with your friends only. That was their big promise. Over time, they switched the default privacy setting to public so that if you still wanted to keep Facebook for friends only, you had to manually find over 100 settings on multiple hidden settings pages. Then, they started dropping those settings and forced information to be public anyway.
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You might have noticed Facebook ads with your friends’ endorsement under it. Basically, Facebook gives advertisers the right to use you as an endorser, but you have no control over it. It’s not limited to when you’ve actually clicked a like button. There have been known cases of vegetarians endorsing McDonalds, a long- and happily-married woman endorsing dating sites, and even a young boy endorsing a sex club to his own mother!
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Using Facebook means this happens all the time. Advertisers can buy your endorsement on Facebook and your information from third-party data brokers. You never get to know about it, and you can’t turn it off.
Finally, I want to explain how this latest privacy change makes things way worse, and way more out of your control if you stay on Facebook.
Facebook is demanding to track what you buy, and your financial information like bank account and credit card numbers. You’ve already agreed to it in the new Terms Of Service. It’s already started sharing data with Mastercard. They’ll use the fact that you stayed on Facebook as “permission” to make deals with all kinds of banks and financial institutions to get your data from them. They’ll call it anonymous, but like they trick your friends to reveal your data to the third-parties with apps, they’ll create loopholes here too.
Facebook is also insisting to track your location via your phone’s GPS, everywhere and all the time. It’ll know extactly who you spend your time with. They’ll know your habits, they’ll know when you call in sick at work, but are really out bowling. “Sal likes 2pm Bowling at Secret Lanes.” They’ll know if you join an addict support group, or go to a psychiatrist, or a psychic, or a mistress. They’ll know how many times you’ve been to the doctor or hospital, and be able to share that with prospective insurers or employers. They’ll know when you’re secretly job hunting, and will sell your endorsement for job sites to your friends and colleagues – you’ll be revealed.
They’ll know everything that can be revealed by your location, and they’ll use it however they want to make a buck.
There's much more at the link. Highly recommended reading.
As LifeHacker pointed out, 'If You're Not Paying for It; You're the Product'. Facebook exists, and makes so much money for its owners, only because its users allow the company to exploit them in every conceivable way (and a few that the average user can't conceive at all). That's why I'm not on Facebook. I refuse to allow myself to be exploited in that way. When browsing the Web, I do my best to prevent companies from tracking me and recording my activities, even though I know I can't possibly be fully successful; and I try not to use any Web site that relies on exploiting me and my personal information to make a profit. I even use an Internet search engine (DuckDuckGo) that explicitly promises never to track or record my search preferences.
Unless we all try to retain whatever shreds of digital privacy are possible in this day and age, we may as well give up all pretensions to privacy of any kind. Facebook, Google, Microsoft and other Internet giants are among the most egregious offenders against privacy. They've already invested millions in 'lobbying' (i.e. 'buying' legislators), to ensure that they won't labor under legal or regulatory restrictions on their activities. We don't have their monetary resources . . . so the least we can do is fight back by refusing to comply with or assist their invasion of our privacy.
As Bruce Schneier put it in his essay, 'The Eternal Value of Privacy':
Too many wrongly characterize the debate as "security versus privacy." The real choice is liberty versus control ... Liberty requires security without intrusion, security plus privacy.