Like others have said, in our house we don't jump on couches or beds. It's not due to the injury side of things (although when DD1 was learning this rule and did jump occasionally I did worry about her hurting herself), but because its not an acceptable thing to do. You don't see people jumping on chairs and furniture out in public or at any of my friends houses, so we don't do it here. For us, it's about learning the rules of society I guess.