With this episode, we see a pattern appearing with the trips the doctor takes his companions on. only with martha and later donna, it's reversed; rose got to go to the future with both his ninth and current incanations, while martha got 1599 and Donna, Volcano Day in Pompeii. The writers seemed to have based the carrionites off the three witches from William's play, but are named Bloodtide, Doomfinger, and Lilith. To those pondering why Lilith can take true human apperance at times, while her 'mothers' can't, maybe she's only half carrionte; their speices devour thier male mates, so its a posiblity.
If anyone else didn;t notice this, but what's up with the 'witches' always speaking in rhyme? i know its how the sceince works along with the shape of the globe, but it gets annoying after awhile. According to the Doctor at the end of the episode when he gie Will his signature 'neckbrace' he's given him 10% of his material, while he seems to have royal ticked Liz 1 off in his personal future since she ordered his beheading after just seeing him. The Doctor one again says 'What? What!? WHAT!?"