Fractured worlds and world souls

In World of Warcraft , we've come across several shattered worlds, in varying degrees of obliteration. From Outland to K'aresh, these worlds have been corrupted with various forces, were shredded into near-oblivion, and some looked as though they may have some kind of shot at redemption against all odds. But what about their world souls? How does each world soul relate to the creation of these…