Censorship is a violation of the first amendment, pure and simple. Kids are going to hear swear words, no matter how sheltered they are. Hearing a swear word doesn't make a kid go crazy, hurt their health, or harm them in any way. Most, if not all, TVs today are equipped with parental control, anyway.
If a person uses a swear word in the wrong situation, it can make them appear ghetto, low-brow, low-rent, vulgar, or however you want to say it. That is a lesson that is up to parents to teach their kids. I say, bring back parental responsibility, and leave the Bill of Rights alone.