Content_ed - 4:37 pm on Feb 25, 2011 (gmt 0)
They may have whacked eHow good, but they did it in part through a crude duplicate content filter. I'm seeing long established sites getting killed because they have been ripped-off, copied and rewritten/repurposed to the point that Google can't tell who was the original. It's basically a duplicate content penalty that is being assessed on the whole domain, rather than on a single page. I even read about one site that has more links FROM eHow than it has pages, and it got creamed more than 50%.
For anybody seeing the penalty who thinks the drop is 30%, check your visitors stats and you may be surprised to see it's over 50% when you look at U.S. only. Keep in mind the change has only been rolled out in the U.S.