The prophecy claims, that one of the Children of Time will die in figh against Davros. For now, I'm assuming what most of people are - that Children of Time are: Captain Jack, Sarah-Jane, Martha, Donna and of course Rose. It's possible, that Mickey will come back, but for now, let him be. He's the tin dog anyway (forgive me K-9).

Captain Jack just can not die. Plain and simple. Kill him, wait a bit and repeat. He's out of the list. And with him being the Face of Boe - a paradox.
BBC has confirmed the second season for "The Sarah Jane Adventures", so she'll be kept alive also.
After that, things start to get interesting. First of all - Martha. There isn't a real reason for her to die and there isn't a real reason for her to live. She's got to prove herself jet - maybe with some heroic dying?
Then there's Donna Noble. She's been really fun and not being madly in love with Doctor is a great advantage for her chracter. That member of The Shadow Proclamation with "I'm sorry for your loss, which is yet to come" confused me though. Would it be that Donna will have to die for the second time in a row?
And then there is Rose - the most faithful companion. The Doctor has died for her twice now. In Doomsdays confidential two years ago some guy said, that DW isn't about death etc. This could mean that Rose is transported back to the beach (crying again) and she is dead for our universe. Or BBC has changed its mind in "no killing companions" policy and kills Rose (crying again).
I know that there will be some kind of twist, which will crush my theory and that's ok. It's going to be a sad episode anyway. Or not.
I also find it amusing, that I have Dalek mood icons. I should get (or make) something "good" side related.

I really need a hobby. Ideas?