At Yahoo!, a designer I work with calls everything that opens up on mouseover "expando" which makes these expando tabs, and the previous breadcrumb entry, expando-breadcrumbs.
First, let me say as tabs go, these are pretty good ones. They have a nice tab shape, the separate types of content, and important-yet-oft-overlooked, the on-state is the same color and connected ot the modified item, connecting the tab to the thing classified.
Now on to expando: saves space. doesn't work on everyone's computer (because it requires javascript), but clicking the tab brings you to the top level category, and the sub-items in the expando are repeated on the left (though that design is rather week) so like the expando-breadcrumbs I'd cry no harm, no foul.
small extra note: article tools are handled very subtly (caught as a bonus in their screenshot) and arrows pointing to text links.