taberstruths - 2:18 pm on Jun 6, 2013 (gmt 0)
My first thought is asking the question of "Why would there be a sudden rise of websites with minimal backlinks?" The obvious answer to me is that there has been a change in what G is looking at concerning link profiles.
More than likely it has to do with link velocity, what is a natural link percentage with no link building based on keyword search volume and traffic, and category of site link norms. I can see where different types of sites would have different norms.
Those are just my initial thoughts as to why sites with what we would call traditionally weak link profiles all of a sudden got power.