A thread at Uncommon Descent addresses an argument that Richard Dawkins raises in his book The God Delusion viz. that if a cause must be at least as great as its effect, and if God is the cause of the complex design of living things, then God must be more complex than living things. So, if, as intelligent design advocates argue, complex information demands a designer then God must have an even more complex designer, which must also have a designer, ad infinitum.
This argument has been repeatedly refuted by far more capable people than me, but I'll take a shot at it anyway. The basic flaw is that those who employ the argument fail to understand what is meant by the term "God." For instance, complexity is a property of material objects or perhaps abstract ideas. God is neither of these. He's not the sort of being that has parts, as material objects do, nor is God, as opposed to the concept of God, an abstract idea. Thus, to impute complexity to him is a category mistake.
Moreover, God, as conceived by most philosophers of religion, is a being possessing maximal greatness. If such a being exists it would be a necessary, not a contingent, being. I.e. it would be a being which, unlike contingent entities, is not caused by any other being. If it were caused by something else it would not be maximally great. God, therefore, if he exists, is the ultimate cause of all being and is himself self-existent and uncaused. To speak, as Dawkins does, of a cause of an uncaused being is to indulge in incoherence.
But, even if one accepts Dawkins' argument that the cause of the world must itself have a cause the argument does little to advance the atheist's position. Since there is personality in the cosmos, at some point along the regress of the cosmos' causes it's reasonable to assume that there's one cause that itself possesses personality. Furthermore, there must be a cause in the regress that is extremely powerful (able to create worlds ex nihilo), extremely intelligent (in fact, a mathematical supergenius), personal, and transcendent.
That's not yet the God of traditional theism, perhaps, but it's very close. So close, in fact, that the atheist who posits this infinite series of causes in order to confute the intelligent design hypothesis must acknowledge that if such a regress exists it would make atheism pretty much untenable.