It isn't some great new threat to the church, just another person unearthing gnostism to offer us a cost-free Jesus...
Endless books have been written about The Da Vinci Code. All a little unnecessary. Its a good blockbuster type book. Save your cash and have a look at this:
Westminster Theological Seminary have put together this website with some good stuff on it if you do want to think about it by people like Garry Williams, Tim Keller and Darrell Bock: