As a content creator, I am very excited about the ability to edit posts that require it. I also have a feeling that AppBase will be great for developers. But if I recall correctly from a post from a couple of months ago, it is the Rocksdb that is really the biggest deal here. I believe that is the same technology that Facebook and Yahoo uses. That means that this is a step in the direction of being able to support a huge user base.
It looks like this announcement should make many different groups here very happy. You are putting those groups in a position to all pull on the same rope (in their own unique way) to help this project grow.