I predict that if Facebook becomes too commercial, it'll die.

It is and always was an entirely commercial operation, selling a product to customers. But you have to understand that
(a) the customers are the advertisers
(b) you, the user with facebook account, are the product.

By the way, the content of the message referred to in the first post is correct. Facebook have always collected what you "like", where you go on facebook and who your friends are so they can target your adverts. The new development is that they can now get your browser to send back your browsing history, so they know everywhere else you've been ou the web and thus know much more about your interests.

I don't do facebook.