WebmasterWorld senior member, steveb, said:
And now it has all completely changed to a result set similar to what wwas around a week ago.. gone are all the trivial bits of nothing.
Senior member, Walkman, adds:
Either way, I would guess that this is an algo update so some sites will come back for good.
WebmasterWorld moderator, tigger, concurs that this seems to be a reversal in a week or two and mostly impacting one keyword phrase searches.