Smith admitted that he knows very little about the series and which guest stars could appear.
"Hopefully we will get some fabulous actors in. I don't know anything about who they are looking to get," he said.
He added: "I've got a couple of scripts coming to me this week - the first ones that we are going to shoot, so I am excited.
"It's funny because I'm in a similar sort of position to the people that watch the show because I literally don't know anything until I get the scripts."
Over the weekend, it was confirmed that the 2011 series will be broadcast in two parts - with one block shown in the spring and the other in autumn. Moffat teased that this would allow for an exciting mid-series plot-twist and cliffhanger.
Smith will next play the Doctor in the upcoming Christmas special.