A Humble Rebuttal:
God was active in the writing of the scriptures. One of the crux's of Christianity is the "inspiration" of scripture. In other words; while the specific words of Paul, Luke, Moses etc were their own, the ideas behind those words came from God. This idea is represented in II Tim 3:16, II Peter 1:20-21 and Deut 29:29. The Bible is God's special way of revealing himself to us. It was written over a period of 2000 years, by more than 40 different authors. God was not only present when the ideas were put down, but He has been present throughout time, ensuring that those ideas remain accurate into every time and every translation. Ehrman obviously does not subscribe to this belief. He must believe that immediately after having inspired each of the scriptures, God abandoned them and left it up to fallen, sinful human beings to preserve them for generations. This is not consistent with the sovereign God represented in both the Old and the New Testaments. Just as God was sovereign in the time of Abraham, Moses, King David, and Paul the Apostle, He was sovereign in the time of Socrates, Ceasar, Charlemagne, Henry VIII, and Napoleon, and He continues to be sovereign today. And just as the scriptures were important to the people of the first century, so are they important to us today. God would not have abandoned His inspired, special revelation, just as He has not abandoned us.
Here are a few better rebuttals to Ehrman. I have not read them, but will try and figure out which one is best and purchase it. Look for a review later on.
By Dillon Burroughs from Dallas Theological Seminary