Using Better Blogs - Cloud
The Better Blogs configuration is found in the Space Settings menu, under the Integrations tab.
From there you will see the Better Blogs app tab.
Once on the tab, groups and users can be added to subscribe them to all new blogs in the space.
By subscribing groups of users, any new user who joins that group, will be automatically subscribed.
When someone creates a blog, all users in the list of groups and users will receive a notification.