They need to have one button to easy opt out.
Regarding the many discussions of facebook and other sites collecting and publicizing marketing and profiling data:
One point I haven't heard mention yet is that the problem is worse than opt-in vs opt-out.
The problem is the insidious allowance of the "Who needs privacy anyways?" trend to gain momentum and reach a point of too-late-to-bother-trying-to-return (because so many sites will have so much info, and so much of it will have already been made available and gotten distributed too widely to ever delete it) long before the time most people finally get burned, or just mosquito-bitten-to-death, and realize how it came to be.
At some point fairly soon, what this will mean is that the mere act of opting out (or declining to opt-in) to data publication by social web sites, or turning off Lattitude, or failing to check in to foursquare, will ITSELF be a big red flag item that will arouse attention and speculation and carry more stigma than whatever you might have been doing or place you might have been going.
This is already happening to money. You almost can not actually conduct your life using _only_ cash any more. If you try, you must be a wacko or criminal with something to hide.
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bkw

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