GitHub has changed it's header color from old silverish background to full black background.
Similarly, Stack Overflow also has updated it's navbar UI. I totally liked these new navbar interface and I'm totally digging it.
Recently wired.com has also published a news about how Linkedin is changing it's interface and making it look like facebookish. More at: https://www.wired.com/2017/01/new-linkedin-looks-just-like-facebook-smart-move/