UPDATE: MARCH 30, 2010 – Click here for the first official photos of the new TARDIS interior!
However a few clues have slipped out – we know that the console room will be split over several levels, linked by a spiral staircase. We are also promised we will finally see some other of the TARDIS’s other rooms for the first time since the series was revived.
This is the view from outside the TARDIS looking in (a cloth backdrop is used during filming to give the impression of a large interior):
This is taken from the BBC trailer for the new series and appears to show The Doctor sitting in a swing seat on the upper level of the console room:
And finally, for now, from fan website Inside The Tardis, we have this, which appears to be the wardrobe room (EDIT: oops, just realised that this is actually the old (9th/10th Doctor) TARDIS, from the scene in The Christmas Invasion in which 10th Doctor David Tennant was choosing his new outfit):
Watch this space (including Time And Relative Dimensions)..!