BBC reports: "The FBI is contacting more than one million PC owners who have had their computers hijacked by cyber criminals. ... The initiative is part of an ongoing project to thwart the use of hijacked home computers, or zombies, as launch platforms for hi-tech crimes. "
I applaud the FBI for taking this action, and having the foresight to realize that it can also be exploited by fraudsters to steal your personal information. Here is a excerpt from the FBI press release on how they will handle the situation: "The FBI will not contact you online and request your personal information so be wary of fraud schemes that request this type of information, especially via unsolicited emails. To report fraudulent activity or financial scams, contact the nearest FBI office or police department, and file a complaint online with the Internet Crime Complaint Center, www.ic3.gov.
If you want more information about Botnets here is article from Wikipedia about it.