My two cents worth, sure to be unpopular:

I own dogs. I keep my dogs on my property. They are NEVER allowed to run loose, in my neigbors' yards. If my neighbors wanted dogs, they would get their own. My dogs are my responsibility, and I would never subject them to danger running loose, nor would I subject my neighbors to their presence.

So WHY do cat owners think it is different for them? I'm sure some cats are happier running loose around the neighborhood. My dogs would be happier running around loose, too ... peeing on everything, digging up flower beds, pooping on other people's grass. I do not, for one second, however, think that my dogs' happiness gives me the right to intrude on the rights of other people.

My neighbors' cats use my flowerbeds for litter boxes. They scream and yowl all night on my fence. They have kittens in my shed. If I would have wanted to deal with all this, I would have gotten a cat. It's not fair, and it's not right. I don't park my car in my neighbor's garage. I don't let my kids go into my neighbors' yards and break things. I don't let my dogs run amok on my neighbors' property. WHY, just because it is a cat, is it somehow different? It is NOT.

I don't care if it is a child, a dog, a cat, a rabbit, a ferret ... if it belongs to you, keep it on your own property and don't invade the space or property rights of others.