All of the arguments I've seen about this so far have tended to go on about "the 50 states" and "the First Amendment". But Livejournal is an international community, with many users from Canada, Europe, Australia and New Zealand. So I don't care about First Amendment "rights", because I don't really understand what they are. Instead, I want to point out the mistake in livejournal's current reasoning.
This is what the livejournal FAQ looks like at the moment. Notice it's been updated as of 2006-05-20.
What are the content restrictions for userpics?
Your default userpic is viewable throughout the LiveJournal site, and unlike individual journal entries, it cannot be hidden or protected. It is potentially available to anyone on the Internet who randomly browses the site. Therefore, we require that your default userpic not contain anything too explicit. In particular, icons which contain nudity or graphic violence tend to be inappropriate for default userpics. Strong language on an otherwise appropriate userpic generally does not make the userpic unsuitable for a default userpic.
Non-default userpics can contain images which are more graphic in nature, and the Abuse Team generally will not intervene if a user is posting with a graphic non-default userpic. If you are receiving comments with a graphic non-default userpic, you may wish to delete the comments; similarly, if graphic non-default userpics are being used on community entries, you should speak to the community maintainer(s).
Note that anyone can see all of your userpics at http://www.livejournal.com/allpics.bml?user=baratron. If you have questions about the acceptability of your userpics or you would like to report an inappropriate default userpic, please contact the Abuse Team. You may also be interested in the standards of indecency for journals.
May 20th, 2006 (rahaeli)
Note the specific wording of the FAQ. In particular, icons which contain nudity or graphic violence tend to be inappropriate for default userpics. Speaking as a European, I have to say, OMG WTF? Breastfeeding is nudity now? When did that happen?
Whenever I run up against rules that involve "but everyone knows what x means"-type logic, I get made uncomfortable. If I can't understand a rule, I might break it by accident. Saying something like "well, everyone knows what nudity means" doesn't actually make sense to me, because what nudity means in my country is not the same as what it means in other countries. For example, topless sunbathing is de rigeur on beaches in the South of France - and I mean that it's not just usual, it's expected. You'll be looked at strangely if you wear a bikini top, and possibly hear a muttered comment of "ah, les anglais". Scandinavians happily strip off in mixed-gender saunas with strangers. So what does nudity mean from an international perspective? In some countries, women are expected to cover their heads, in others both men and women are expected to dress modestly and cover shoulders. How can livejournal ban "nudity" without first defining it?
I feel that if livejournal is to say icons which contain "nudity" are inappropriate for default userpics, they need to define which parts of the body count as "nude". I am presuming that naked heads and hands are allowed, simply because no one's ever complained about those. What about naked arms? Backs? Legs? Bottoms? (I'm guessing not bottoms.) If I took a picture of my naked legs, that would be nudity, wouldn't it? Especially if all of me was naked at the time, but I cropped the image to only show my legs. So is that ok? If it is ok, why is that ok, but my naked breast isn't? How about naked babies? Are they allowed? Is the issue about the breastfeeding mother nothing to do with her breast, and actually to do with her baby?
You might think I'm being deliberately stupid for the sake of making a point, but I'm not. People need to understand rules in order to obey them. This is particularly true for livejournal users who have disabilities such as autistic spectrum conditions, for whom things which are "obvious" to "everyone else" do not make sense. I have several autistic friends on my lj friends list, plus many other friends with other disabilities who love the internet as an accessible means of communication. Livejournal is a tool for keeping people in communication with each other, and rules must be understandable to all livejournal users - including those who have disabilities.
I believe that, rather than simply saying that nudity is not allowed, livejournal must define the parts of the body that must be covered in default userpics, and also specify explicitly whether this restriction applies only to photographs, or also to icons of paintings, cartoons, or screenshots from video games. If it is indeed the nipple that makes the breast indecent, then that argument must apply to men as well. (I'm reminded of the Aerosmith album "Get a Grip", which has, as the CD illustration, the nipples of the five band members.) And it must be consistent.
I would post this to livejournal Customer Service if I could find a direct link - Contact Info seems to send you round in circles to direct everything through lj support, which really doesn't seem like the right place for this. It needs to be sent to the policy makers, not the enforcers. Update.