I've read a few articles about it now. The three big heavy hitters in the worm leagues are duking it out, up to and including insult messages in their latest versions for each other.

The truly significant message is something like the following: "You're going to ruin our business. Do you want to start a war?" All of the pundits don't get it... they are still in the mode that this is about vandalism, when in fact the motivation is commercial. This is all about installing mail forwarders on compromised machines, so that a spammer can send out 200 emails (using "200 X sizeOf(emailMsg)" as bandwidth consumed that they have to pay for) and having it hit 200 million email boxes. Potentially, it's very big business, and it shows with the increasing sophistication of the antifilter techniques used in the email messages themselves as well as the distribution networks for the spam. Apparently the three main parties that control the majority of compromised boxen out there are now releasing versions that disable/delete competitors on the infected machines as well as infecting new machines.