That was beaten to death many years ago. Nobody with a half neuron will argue for filtering or removal of those newsgroups on a large scale (now, i contend that a teeny weeny ISP can get away with it, but for large ISPs it just doesn't work). The reason is very simple: the objectionable content will simply move to "legitimate" newsgroups. There is no way to prevent it.
Vadim, This may be true in the US, but if you are in Canada, you must prune these groups, particularly the kiddie porn, regardless of migration of content or any other technical issue. And if customers complain, you must act on them, instead of claiming some non-publisher status. I have been in way more legal briefings than I care to admit on this issue, and its a done deal here in Canada. If you do not act, as some smaller ISPs have not, you are law enforcement cannon fodder. Kiddie porn busts make the major networks' national news here, particularly when the Internet is involved. Eric Carroll eric.carroll@acm.org Tekton Internet Associates