Ahhh I see what you mean now, the microblogging tab within the actual magazine? Sorry, I am still getting used to all the features on Kbin!
I think I know what's going on...
Each magazine has a set of tags listed on the side of the screen, and it seems the microblogging section of a magazine displays posts with the tags that the magazine has chosen.
So, it's like the magazine has subscribed to hashtags and is displaying this feed in its microblogging section.