Today, September 23rd, 2016, Google announced that the Penguin has been rolled into the core algorithm. The Penguin update has historically focused on the quality of off-page metrics pointing to a site. This means two big things for SEOs:
In January of this year, Panda was rolled into the core algorithm. While Panda metrics are typically focused around on-page optimizations this has brought more stability to SERPs, especially to pages putting in the effort for quality content.
The update is still rolling out, and there’s bound to be some shifting in the SERPs over the weekend and the coming week. It will be interesting to see the effects of the said update.