The Matrix wasn't actually all that original. It's just that the ideas were presented to a mass audience for the first time, and a lot of people won't have seen the stuff it's derived from, so would see it as something exciting and new.

It's probably the same for The Da Vinci Code... very little of it is new (the theories, etc have been around for a while), but it's the first time they've been presented to a mass audience.

Maybe that's why they seem intelligent.