Well, The Curator did say The Doctor might revisit a few old faces and By Jove he seems he was right. At least for one small scene they have recorded for the imminent release of Shada on dvd. I am not sure of the context or how this Doctor fits into the story, beyond a knowing wink and that marvelous smile that speaks volumes across the ages
Never thought I would see that old face in that old console room.
I don't know about you but its done me a power of good.