If you are in a car, with an inexperienced driver, and at one point a CD case flies up and hits you in the face during a turn, what sort of injuries would that leave?
Unless you're going at a very high rate of speed and in a very bad accident, where a flying CD case might cause the least of your injuries, in general, it would be the same as if someone threw it at your face. Now, there is the problem of projectiles, going at a very high rate of speed, and therefore causing more injuries than they otherwise would. But I find it hard to picture where a CD case would be placed where it would be high enough to hit someone in the face and being far enough away to cause serious injury. The worst I could think of would be if the corner got someone in the eye.
Laceration, definately. Depending on how fast the CD flies effects the deepness of the cut. Unless you're writing a splatterhouse piece it's unlikely to hit bone.