I am creating a website for a Christian Speaker. She wants people to be able to subscribe to specific blog categories. For example, she has a blog category specific to the health of her daughter that many friends and family would like to follow, but they might not be interested in receiving email notifications on other religious blog topics that clients may.
I have included your need in the features Wishlist, it is not possible as for now.
Currently you can manually send the Shoutout announcing the specific post.
Thanks for sharing your needs!