For starters, when the series returns in 2011, it will be one long story made up of 10 episodes and it: "will have a very American flavour. Most of it will be shot and set in the States (or other foreign countries)."
Davies didn't want to talk about the story yet, saying that : "It’s too soon to give away the story, but I’ve always had this story in mind, and the whole existence of season four will make sense once you know what the story is."
Davies confirmed that he wrote the first episode of series four of Torchwood but that as for writing more episodes for that, it's still in the air.
The Torchwood showrunner went on to talk about the very successful recent series Torchwood: Children of Earth:
Actually, this story is also very dark. I think with that, Torchwood found its feet. People found something very compelling and very chilling about it. I love the way people got on their high horse saying, ‘Oh, he killed his grandson!’ Hello! He saved every single child in the world! If you would fail to do that then you’re the monster, frankly. It’s this extraordinary treatment that only science fiction heroes get You find that. If ever a word is said out of place by the Doctor or Captain Jack, or even by Sarah Jane sometimes, people throw their hands up in horror, whereas in any other drama any character is capable of any thing at any time. That’s the only way to write, and it’s the same for these people as well. I thought it was fascinating and challenging what he did there, but hard – it was so hard. I do think with the whole of Children Of Earth we found a new heartland for Torchwood.But as for the upcoming series, Davies also added that:
For faithful viewers you’ll see the same people in the same world, following on. Though it also starts from scratch, because there’s a brand new Starz audience there sitting waiting to be scooped up, new viewers coming to it. But I restarted Doctor Who in 2005 from scratch, so I know what I’m doing. I did it with Children Of Earth, actually – that practically tripled Torchwood’s audience, and no one said to me that they were lost. So it’s a new starting point and yet… as a faithful viewer you do get that awful feeling when something reboots or revamps that you’re not comfortable anymore, and there’s none of that. It’s still Gwen, it’s still Jack, and hopefully more. You’ll feel very comfortable with it. And there’s great new American characters coming into it. Bear in mind, of course, Captain Jack, he’s American as well, so it doesn’t seem quite as alien, I think, as if you suddenly introduced American characters into Emmerdale or something!”Go here for more on SFX magazine's interview with Russel T. Davies.
I don't know what you guys think of this, but I have faith in series 4. Children of Earth was so good though, I just hope they will be able to top it!