Nice opinion piece in the Telegraph on how all these social networking sites can be addicted. Seems Mr Scoble has been hooked. I particularly like these 2 quotes:

Facebook's administrators have access to a database about who knows who, how they know them, their sexual behaviour, favourite movies and what time they are chill: a database of which the Stasi or the Mukhabarat could only have dreamed.

Sooner or later, privacy be damned, the damage Facebook causes to the British economy in lost productivity may have to be offset by the sale of its data to marketing companies.

I did get pulled into LinkedIn but I have too many other addictions and this one did not get a look in against the competition