Btw Russel on a new interview said that Torchwood is not officially cancelled. And that the show can return sometime. Right now he is not doing anything Torchwood related. He is focused on Wizards VS Aliens.
On Sarah Jane adventures he said they thought for 5 seconds if they had to find a new lead for the show but that thought only lasted for these 5 econds, the show was over when Liz left us