Douthat says a reader can choose Christ or Dan Brown, but not both. This would come as a surprise to many people I have spoken to about Brown's novels. Their contention is that it simply a good story.
But Douthat points out that Brown himself does not see it that way. Like Ayn Rand, Brown is using fiction as vehicle to "inform" readers. Here is a direct quote from Brown: "My goal is always to make the character's and plot be so engaging that readers don't realize how much they are learning along the way." http://www.danbrown.com/novels/angels_demons/interview.html