I previously reported on 11/5/07 that MIcrosoft was including a Kill Switch that would check your version of Office or OS anytime you downloaded updates, and that the Kill Switch would activate if Microsoft felt your software was pirated. 

It turns out that Windows Genuine Advantage is not such an advantage.  Several legit copies of Vista have been zapped and users are complaining.  So as part of Service Pack 1 Microsoft will replace the Kill Switch with a Nag Switch.  Per MS VP Mike Sievert,

"They won't lose access to functionality or features, but it will be very clear to them that their copy of Window Vista is not genuine and they need to take action."

Microsoft has seen a drop in piracy for their efforts.  My guess is somewhere down the line they'll introduce an improved version of the Kill Switch.

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