Join this video, the comments here from Black Hat World, and other forums. It seems that we have reached a consensus, that everything has to do with domain authority, whether through links, being a large site (with many pages) or having an old domain.
At least what I've read is people losing positions to Reddit, Quora, .edu sites. Others complaining of losing positions to blogs and large magazines (my case). Some people who invested heavily in backlinks did well. People with sites with few pages are doing poorly.
It looks like Google's "wall" is getting higher for who can reach the top SERP positions.
I already know what the next strategy I will follow if the update stays like this.