It should have been obvious when Rupert Murdoch bought MySpace that there was nothing innocent or meekly – geekly – benign in social networking online. But somehow we managed to kid ourselves that it might be so.

So it was that we spent hour on hour stuffing our Facebook profiles with the sort of demographic and consumer detail that marketers couldn’t buy. And didn’t have to as it turned out, because we gave it to them. Now, with the unerring precision of well-informed ”contextual” marketing, the advertisers are turning social networking to commercial advantage.

The social networking novelty – and its voguish appeal to the world’s politicians and geeks alike – is about to wear thin. Your Facebook friends have asked you a question: Ever get the feeling you’ve been cheated?