Well the thin white duke wouldnt have had a cameo if the sun were to believed. Outpost Gallifrey are quoting David Bowies website, saying that the Sun's story about the David Bowie being an alien in the next season of Dr Who is Bunkam.
Outpost Gallifrey: Doctor Who News Page
Pity really, anyone else you would like to make a cameo or appearance in Dr Who.
I do hear that Bernard Cribbins will be making a cameo.