If adhered to, this will help eliminate some spam. You can easily create a Message Rule in Outlook or Outlook Express, for instance, to delete any message with "Sexually Explicit" in the subject line.
No good. The spammers would just start using variants of phrases like "s.e.x.u.a.l.l.y explicit" and so on.
These anti-spam laws are a waste. 90% of all spam comes from overseas. You think those spammers are worried? Got news for ya...