You're spot on! I left facebook the end of last year precisely for the reasons you mention. I had been intrigued by the way all the photos automatically tag what's there with machine learning.

'2 people, drinks, exterior, greenery, smiling, close-up, tennis.'

It's hard not to imagine someplace in Facebook's headquarters where they head over to the database and filter out pics they want to see, for their own purposes. In fact I actually read an article sometime where they had all kinds of stats based on your account, for instance, they were able to tell with +90% accuracy if a couple was going to break up soon based on correlations of mutual friends.

I watched "The social network" then for the first time. And glad I did it because I could understand what sort of person Mark is. If he was able to rip-off the Winklevoss and his friend like that, then what would he do to total strangers.

Facebook "secret research division" now have plans to send thoughts over the network... not mine for sure, me? I'm out!