A big spammer was cut out of the Internet. 70% of the world's spam seems to have vanished.
I was once told by Olivier Caleff that there could be no decrease in spam, that if you saw a decrease in the number of spams caught by your antispam, it was that your antispam was falling behind the smartness of spammers.
But I think it doesn't apply to this situation. If we don't watch the pessimist side "they will start their spamming business again somewhere else and all that will be for nothing!", that's very good news :-)
Not often a security guy can get happy by reading news.