It's not a package manager
It's a lot simpler than that. It's just applications. In fact, it's just an application storefront that can download and install the things. And keep track of your licences. But there's no uninstallation and no dependency tracking — though per the admissibility rules there are also no dependencies. But it's a technical difference nonetheless.
This is news because (i) it's the first major push to create an electronic store for desktop software; and (ii) some people fear it points to a locked-down future for Apple's desktops. I don't agree with them, but nevertheless it makes the story more interesting for a bunch of people. The story also contributes to the iOS versus Mac OS narrative.
Compared to a Linux package manager, the newsworthy differences are infrastructure (ie, paid apps, lots of commercial developers and commercial release cycles) and prominence. You're right that, technologically, there's nothing new here.
Biting the hand that feeds IT
