SFX has an interesting article on their website regarding the episode entitled 'Vampires Of Venice' written by Toby Whithouse. They have some random facts:
At one point the Doctor says the word ‘diabetic’.
One character is a talking otter.
There is an almost painfully beautiful gag about cheese and biscuits.
One of those isn't true.
Also, when asked if the 11th Doctor will say 'Geronimo,' Whithouse replied, "No, he doesn't say Geronimo! I had no idea that was going to be his catchphrase!"
Thanks to Will from Will and Seb for telling me about this!
They also have an interesting article about the things we learn from the new edition of The Writer's Tale. Read it here.