Lenin - the problem is that you might say something libellous about me -"that BIWI has a huge, spotty arse and eats babies for breakfast", for example - and I can get very upset because that is defamation of my character. Because of course I'm not that fat.
But rather than sue you, I would sue Mumsnet - they (as far as I understand it in the current set up) would be liable for your comments.
The reality of course, is that a discussion forum owner can't/shouldn't be held responsible for the things that have been said by individuals posting on there.
The whole SWMNBN debacle was a good example of this.
Even if MN (or other sites) had official moderators, there are so many threads, posts and posters that it would be impossible to monitor the site effectively. And it would be a massive financial drain - possibly making a site like this commercially unviable.
The consultation, as far as I understand it, is to decide what the possible alternatives are - i.e. there has been a recognition that this needs reform.
(I hope that this is correct, but this is my understanding of it).
Will try and read the rest of it later ...