According to this article on Tech Crunch, a team has now developed a way to make a bump key with a 3D printer. Worse, they can take a picture of the keyhole to make a bump key for any lock. Having a deadbolt with an obscure keyway won’t protect against this technique at all. Even if yours is the only lock in the world with a particular keyway, they could make a bump key for it based on a simple picture.
The only way to overcome this deficiency is to install a lock that can’t be bumped–like the Abloy Protec2.