The two founders' aim is to mine knowledge that isn't already online and put it in the highly social context that Facebook has trained everyone on.

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In recent weeks, the floors in that part of the mine had been "heaving, " or buckling up, from intense pressure, said the source, who has intimate knowledge of the conditions in the mine.

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This recent nugget of polling knowledge from Gallup.com just shattered an illusion of mine.

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