That’s the widget that social media expertards loved which showed the faces of other users who visited their blogs. It was yet another of the slow and annoying widgets in the sidebar. In that respect, I’m happy to see it go, though I frequent those kinds of blogs less and less these days.
As Marshall’s article details, though, there was potential for this kind of thing with respect to analytics. I’m sure a better implementation of the same kind of idea will win out someday.