The interesting thing here is Redmond, where the infected systems' OS comes from.
From http://www.microsoft.com/security/worms/conficker.aspx: "Is my computer infected with the Conficker worm? Probably not. Microsoft released a security update in October 2008 (MS08-067) to protect against Conficker." [snip] "To date, security researchers have discovered the following variants of the worm in the wild. * Win32/Conficker.A was reported to Microsoft on November 21, 2008."
Curiously, the NYT states that the first infections were dated November 20.
So they release an anti-Conficker security update before ever knowing of its existence. No, wait: one month before the very first appearance of the worm in the wild.
Have they invented time travel and didn't tell us? (And, will it be included in Windows 7 as a feature? That's one thing I would pay for.)
By the way, the NYT article says as many as 5 million computers are infected now, in more than 200 countries. MS's concept of "probably not" seems a bit vague to me.