Siobhain Butterworth, the Guardian's Readers' Editor, recently wrote on Comment is Free that:
"It has never been easier to become an author - the web can make instant publishers of us all. There are plenty of places on the Guardian's website where you can say what you think: Comment is Free (CiF) for interaction with comment and analysis, or our talkboards where you can join (or start) discussions with each other...
More than 3m comments have been posted since 2004 - 250,000 of them in the past month. Given the volume it is not surprising that a few postings on some discussion threads have given cause for concern...
...The Guardian is legally responsible for the journalistic material it publishes, but it may also be liable for postings...."
The rest of the article considers the legal position of the Guardian when hosting and moderating online discussions and comments authored by their users. It's also nice to get a glimpse of The Guardian's comment statistics.