Oh dear, Tumblr has updated something and people are Upset.
If I understand correctly, the new update makes it so the person who is notified about a reblog or comment is the latest person in the reblog chain, not the original poster of the top post. I assume the purpose is to A) encourage conversations among people in close reblog proximity to each other, and B) stop viral posts from being overwhelming for the original poster.
The problem is that people can talk about your post without you even knowing. If you post some original art, you don't even really know how many people have seen it. (You don't see the total number of notes, only the number of notes directly from your version of the post.)
It seems to me that an easy fix is to make all this optional. Make a way to see the total notes if you want to. Make a way to get all the notifications if you want to. (Of course, not being a programmer, I have no idea how easy that fix would actually be lol.)
They say they're open to feedback. Maybe I'll write and tell them.