That is in part because Jonathan Browning, head of VW USA, apparently doesn't see the point of expanding VW's product portfolio with another model (a truly unexpected sentiment coming from Volkswagen as far as we're concerned). The U.S. being the largest consumer of sports cars, our sitting this one out puts the 2009 Detroit Auto Show showcar in a tough spot.
Synergies being what they are, that also puts Bluesport's brand brothers from Audi and Porsche in doubt. Audi plans for an R4 will apparently get iced in light of the news, but Porsche might have dodged a bullet: it wanted a four-cylinder 550-successor, but not one that would eat into Boxster sales, which this car almost certainly would. The Bluesport isn't officially dead yet, but at three years in and counting, you can be sure there's a hand on the life-support plug.