There are few blogging platforms built with Node.JS. The best known is probably Ghost. - it's core strength but also weakness lies in it's motto:
"Just a blogging platform"
If you need just a blog, I highly recommend using Ghost, but if you want to run a website or lauch a web app with a blog, Keystone.js is a way to go. It is one of the best CMS out there written with Node.js on the backend. Out of the box generated app comes with blog set up, but it has few flaws - it's not SEO and social media friendly, it has very basic look and no support for social sharing. Read more to see how to fix it with few lines of code and take Keystone on par with Ghost platform.