SEO Book – http://www.seobook.com/blog – Personal guide to increasing web visibility. Great blogs are posted every few weeks, and the author (Aaron Wall) is very active on the site. Blogs range anywhere from tips for optimizing your client list, to debates over advanced SEO algorithms implemented by Google. It has topics for novice and advanced optimizers.
The Moz Blog - http://moz.com/blog – Community blog focusing on SEO, but also addresses topics such as mobile marketing strategies and customer conversion rates. Only site members can post, so it is selective, but Moz Blog is popular enough that there are a variety of members posting daily. The site has been around for nearly a decade and has maintained quite the following.
Search Engine Watch - http://searchenginewatch.com/seo – Search Engine Watch is updated constantly, with multiple posts every day. It focuses on ideas such as Pay Per Click (PPC) advertising, SEO and Internet marketing. This site offers tips and expert search engine analyses. It has a lot of content and is well organized, making it an easy site to navigate.
Search Engine Land - http://searchengineland.com/library/channel/seo – Probably the most active blog on this list, Search Engine Land concentrates on current SEO trends, with user blogs as well as “how-to” guides. Updates include articles from SEO experts, reviews on new Google technologies and programs, as well as Search Engine Marketing information.
Matt Cutts - https://www.mattcutts.com/blog/type/googleseo/ – Matt Cutts is the head of Google’s Webspam team, and he has some powerful insights on SEO ranking. His blog is updated pretty frequently (considering all the posts are from him) and they are helpful with avoiding the creation of spam, as well as how to rank higher on search engines.