I am what I believe people would refer to as a 'dog person'. I like it when they jump up and lick my face (when I come home from work, I'll usually lay down on the couch for my pair to say hello to me: double puppy cuddles!).
However, I am well aware that there are more than a few people that don't want dogs in their personal space at all, let alone jumping all over them. My two aren't the biggest dogs (their heads would only come up to your waist if they jumped up on you, and they're only 20 and 25 lbs), but I only let them say hello to people on our walks if the person makes the first move (we have leash laws around here, so no fear of them not listening) and if they get too excited and jump up, I immediately get them off (it's still something we're working on; we're getting better, especially with children). Unfortunately, because my pair aren't that big, and because most people seem to find them 'super cute', it's been slow going getting them to learn on their own not to jump because most people just let them. They're both pretty high-strung too, which doesn't help.
I know how hard it is to teach your dog not to jump on people first hand (especially the little ones) and how strangers never seem to listen even when you tell them to ignore your dog if they jump ('Don't pet him if he's jumping', 'Oh, okay', dog jumps, pat pat pat 'Don't worry, I don't mind; I have a dog too'), so even though I like having the dogs jump on me, I'll usually put my hands up in front of my chest and take a step back while turning away when they do it, to show them that jumping doesn't get them the attention they want. Most dogs pick up pretty quickly that four-paws-on-the-ground means pets and attention, and jumping up makes the new friend turn away and leave 