Andylew - 2:34 pm on Jun 8, 2010 (gmt 0)
@scottsonline there is a great news article just this second been published on exactly this theme. (I have nothing to do with it)
My latest theory (there have been many these past few weeks!) I wonder whether the algo tweak they have done is an over optimisation algo penalty? Ie sites which appear to be too good to be made by human hand have been given a penalty, it would certainly explain a lot - the naff sites are naff enough to look 'human' so have got up in the listings and in fact it is the well optimised but incredibly useful sites that have been hardest hit using a too good to be true algo.