How are we planning to organise content here?

Kevin,
Thank you for asking - there is a lot of new ways to see existing content.
For the most part this is the same content just displayed differently. Leslie_Hubertus wrote about the site navigation in this article Getting Started on DevCentral - go down a bit to Navigating the Site.

As for Labels and Tags on this platform:
Labels are enforced on new content and represent a very small set-list of high-level organization defined by us: Security, DevOps, Application Delivery etc.
Tags are those free-form pieces that the author may contribute to their own post.

You can interact with these components like this: (added tags are clickable/sortable too) 

You can subscribe to changes for any label (when you click on it)

And you can see articles sorted by tags by clicking on them too. The red bar at the left of a post marks UNREAD.