This time they're doing it the right way:
The Federal Judge allowed them to supplant the Command and Control servers with their own, so when the nasty "dial home" software does, the FBI servers shut the malware down and notify the relevant ISP which sends an email of how to clean out the malware.
This is important because Coreflood distributed financial id stealing software.
If you get an email from your ISP concerning this, do as it describes, and also get in touch with some folks to help repair the damage done to your identity.
The prior Rustock, etc. was incomplete as the software was left on the home pc's and ISP's weren't notified to follow up with their clients.