Tony Jones helpfully points toward a panel discussion at last year's American Academy of Religion on the subject of Creatio Ex Nihilo, or "creation from nothing." The podcast is well worth checking out, as is the ongoing debate on the issue between Tony and Tripp Fuller.
As Tony notes, agreeing with Philip Clayton, the core element at stake in the argument about creation from nothing has to do with the nature and character of God, as well as what implications the doctrine has for how human life should be lived.
There is a strain of argument that asserts that the idea that God is radically seperate from the universe is what allows for the kind of imperialistic, mysogynistic, and heirarchical forms of monotheism that are a big theological problem today. But I would argue (I think in accord with Tony, and with Jurgen Moltmann), that this is a misunderstanding of the way creatio ex nihilo ought to function in Christian theology. It serves not to provide an analogue or justification of human action, but as a testimony to God's radical freedom vis-a-vis creation. It is, in fact, what it means to refer to God as a creator, and to refer to God as a necessary being.
If God is within the univere or an emergent quality of the univere, then God is contingent as the universe is contingent. Yet, a contingent God is no God at all, for that God is not free of the limitations and constraints of the universe of which he is a part. Rather, God becomes a being among beings. This is the central flaw in process theology, as attractive as it may be on many other fronts. Unless the nature of God is that of a being free from the constraints of the universe, there is no way of conceiving of God salvifically, since God is ultimate bound to contingency with all other beings. Such a God is in fact less than the universe itself, since God is limited by the possibilities of the universe. This might be a good description of Galactus, but doesn't do justice to the vision of God embraced within most theistic accounts. This is, in an old phrase, a God who is too small.