According to a couple sites, Nikon has accidentally leaked user manuals for unanounced cameras. The manual for a new entry-level DSLR called the D50 was briefly posted to one of Nikon’s websites. According to this story from MacWorld.com the camera’s existence has been confirmed by the official Nikon spokesperson.
At the same time, Rob Galbraith is reportting that another manual for a camera called the D70s has also been leaked/accidentally posted. Nikon has not confirmed the existence of this camera.
In any case, new toys are fun!