I'm happy to say I have neither read nor paid much attention to all the hoopla around the Da Vinci Code.
The problem is not that someone made up a story and is making some noise in the world for a little while. People do this all the time.
The problem is that many of us don't know our own faith and that we have lost a sense of a catholic culture. And when you don't know who you are, anyone fool is free to come and tell you. We suffer from what Cardinal Poupard has called religious illiteracy. You can check out what he says today in Zenit.
To address this situation is critical if we are to be able to "give an explanation to anyone who asks us a reason for our hope." (1 Peter 3:15) Perhaps the Da Vinci Code is a grace to help us recognize our need.