Okay, you have been warned. You have the choice not to go on.
So, still wanna know?
Your last chance.
On this thread (you need to sign up, but if you're a serious spoiler hound, it's worth it) in the Outpost Gallifery forums, infamous scooper Scooty has snapped a pic of David Tennant's Doctor in a (what looks like contemporary) book shop where there's a signing for a book with a very telling title... and author: A Journal Of Impossible Things by Verity Newman. And if that doesn't get you all excited we suggest you watch "Human Nature"/"Family Of Blood" again.
Blimey. That's an exciting development we weren't expecting.
Meanwhile, Planet Gallifrey has a ton of new pictures from "Planet Of The Dead" including this guy:
So, does the episode also feature a fly with a scientist's head, crying, "Help me! Help me!"?