A certain actor who has played a past Doctor Who villain was spotted around filming for the 2009 specials.
John Simm!
From reading the set reports on
DWF, I believe that he hasn't been actually seen filming anything yet, but HOLY CRAP!
If you go to the source, you can see more pictures of filming for all of the 2009 specials. Also, the person who takes the pictures has a twitter and updates with set reports, which is located
here.
source