Don't worry about it, when it happens you'll know. But you'll be in a boat with so many millions of others that knowing still won't make you care.
Just relax and go back to your content consumption with the other sheeple.
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rmwebs on reply number 7.
Wow how smart you must be
Firstly, at what point did I say I trusted anyone? This is the internet. You'd be a brain dead idiot to trust Apple, Google, Microsoft, heck even MacRumors.
My point remains, despite your feable 'sheep' comment (which by the way still didnt answer the question I put forward).
Lets look at a hypothetical situation:
Google.
We already know that (unless you opt out) Google log your search history and browsing habbits (on sites that have adsense or analytics). So from that they can build a sort of profile saying "hey IP address 123.456.789.000 using Safari seems to like looking at sites about Tennis." Then if you're loggec in it can track it back to your Google account.
Now, obviously there isnt someone sitting there going through this info checking up on people as that realistically would be impossible.
So, at the point, Google knows that you like Tennis and uses it to show ads for local tennis shops, tennis gear, etc.
Thats it. You've hit the dead end right there.
There is nothing else that information has ANY use for. Google dont sell it - we know they dont. The same as Apple dont sell info collected on iAds, and Facebook dont sell info on your likes.
Selling the information would actually be detrimental to their own business plans. Why sell it to someone once when you can license it in a way that doesn't violate your privacy? All they do is get an advertiser to pick targeted keywords, then if a keyword matches one of the keywords built around your habits, it shows the advert in hope that it'll be relevant.
So. I'll ask the question again in a slightly different way just in case people still dont get it.
Google knows you like Tennis, and use it to show Tennis ads to you.
Why is that a problem? At what point is that putting your life in danger, or causing distress to you? It's no different to sticking an advert for a taxi company at a bus stop.
If you're really that paranoid about your personal info that you avoid the likes of Google, Facebook and Apple you really shouldn't be on the internet.
Maybe you shouldn't be on MacRumors. After all they use viglink, like most forums - Viglink knows you like Macs, and a smaller company are much more likely to get away with doing something dodgy with your info than a company that has the eyes of the world watching them.