Beware of Dog?

It's not uncommon to see a "Beware of Dog" sign. Some are more inventive than others in their wording, some are specific bodily threats to intruders, and some say that it's best to watch out for the owner.

I see a lot of discussion, though, on what signs like that mean for owner liability. You see articles of cases in which a burglar breaks into a house, hurts himself, and then successfully sues the family. You can imagine such a thing makes a dog owner nervous. "I broke into the house and was carrying out the TV when their dog bit me! I'm suing them for a million dollars, and so that the dog gets put down!" I read things like that and think "really?" It can happen though.