Dr. Piper Harron is now blogging for the American Mathematical Society. The AMS has several blogs of interest to mathematicians, including graduate students (AMS Grad Student blog) and early career faculty (PhD + epsilon blog). A full roundup of AMS blogs can be found here: http://blogs.ams.org/
The newest AMS blog is called inclusion / exclusion; it’s a blog about underrepresented groups in mathematics. The first blog post by Adriana Salerno introduces the blog and the editing team: http://blogs.ams.org/inclusionexclusion/2017/02/06/inclusionexclusion-principle/. Dr. Harron’s first post just went up: http://blogs.ams.org/inclusionexclusion/2017/02/22/hands-off-my-confidence/.