Google is still recommending that you nofollow your credit links in your footer, if you have control over those links. So the site designed by or powered by or made by types of links, nofollow those ...
This week, we had two different Googlers answer questions about link placement on a web page and how it differs having links in your main body content versus links in your footer, header, boilerplate ...
A long, long time ago I was talking to Mike Grehan about search engine rankings. He used the term “the rich get richer”, to explain why sites that live at the top of Google are likely to stay there.