Has the CAN-SPAM law, now about three years old, made a difference?
In 2003, I was receiving about 16,000 junk emails per year. 2003 was also the year that several state anti-spam laws went into effect. By early 2004, the annual volume had dropped to 10,000, a reflection that the spammers were adjusting to meet the stiff requirements of state laws like California's.
2004 saw CAN-SPAM go into effect. The federal law took precedence over the better, stronger state laws, all of which then went out of effect.
The result? My measured volume right now is over 40,000 per year.
That number does not begin to reflect the actual volume of junk reaching my hosting company's server. Spammers and those nasty virus guys, having found a responsive domain, make up email addresses within that domain and attack, hoping that something gets through. One of my small clients' internal mail server receives about 4,600 emails per day and rejects over 90% of those. That's 1.5 million pieces of junk per year to one small business.
CAN-SPAM is junk. I call it the Yes-I-Can-Spam law because its result has been more, not less, spam. Worse, CAN-SPAM prevents individuals from taking any legal action against spammers, leaving that in the hands of ISPs and government agencies. Government hasn't done much. There have been a couple of suits from ISPs but those targeted specific business issues, not the more general problem.
BAN-SPAM! Think that's a violation of free speech? Did you know that it's illegal to send an unsolicited fax? Check it out, then write your representative.