I'm in the minority here, leaning towards a greater tolerance for "impolite behaviors". I say "impolite" in quotes here because I personally do not view jumping as an impolite, inappropriate behavior, just as hopping around on furniture is a perfectly acceptable behavior in a dog for me. Obviously, I understand that MOST people do not share this opinion, so if they want to greet him, I'll tell them "he's exuberant and jumps on people", and if they still want to pet him, by all means go ahead. If they don't want to, I don't have a problem with that. Trent doesn't go around jumping on strangers every time he sees one, he'll jump up on people I allow him to greet, and if he decides he likes them (he's still got that puppy exuberance, but some of that selective aloofness is coming on).
My dog should not be required to act a certain way so everyone and anyone may run up to him excitedly and pet him. He isn't public property, but when he IS in public, he is not a nuisance either. He minds his own business and behaves appropriately. But if you want to come up and pet my dog, don't expect my dog to act according to YOUR standards.
With kids and the elderly, however, he inherently understands the need to be careful around them. He is very, very gentle with them. He may wag his tail like crazy, but he will never once jump or paw at them. He does give kisses, and I will warn kids petting him that he likes to lick and can be slobbery, but haven't met a kid yet who doesn't like puppy kisses.
