VNS, and the television networks it works for, failed so spectacularly because it didn't factor in the massive shifts in how Americans vote. Brill's Content gained access to VNS documents, including screen grabs of the VNS numbers that resulted, first, in the calling of Florida for Vice-President Al Gore and, later, the calling of the state, and the presidency, for Texas governor George W. Bush. Network and VNS officials have been predictably parsimonious with their comments, but the VNS documents, combined with interviews and transcripts of the networks' election-night coverage, explain how a multimillion-dollar project designed to serve the public ended up doing exactly the opposite.
http://www.brillscontent.com/2001feb/features/mnookin.shtml