here are a lot of rumours about the episode that follows The Next Doctor, but what can we consider true and what is speculation/rumour? I've read through everything I can find, and here is information that has come fromlegitimate sources, so they can be considered probably true!
The title for the first Doctor Who Special next year will be revealed at the end of The Next Doctor - as they haven't started filming it yet, don't expect a clip :) (DWM403).
It will be shown around Easter 2009 (Julie Gardner).
The Doctor will be traveling without his TARDIS and without a companion (Radio Times Xmas issue).
The title is four words long and one word begins with D, the story will be one hour long (DWM403).
Phil Fords script contains the words Emily, pipes, carrots, legend, gadget and concerto (DWM).