It's fair to say that Torchwood: Children Of Earth has proven to be something of a success for the BBC. Torchwood had, over the its first two runs, managed to increase its ratings, but the switch to BBC One, combined with a five episode arc over five nights, can easily and fairly be described as a triumph. Aside from perhaps the penultimate episode of this year's Ashes To Ashes, it's the best thing we've seen on British telly all year.

This, of course, inevitably led to speculation over a fourth series for the show, which Russell T Davies had earlier suggested was ready to go, awaiting a green light. Well, given that Children Of Earth has now also enjoyed success in America, it seems that the nod has been given for further Torchwood adventures, even if it's not entirely clear just yet what form they will take.

Leaving aside the fact that Captain Jack has fled the planet, meaning a pregnant Gwen is the last surviving member of the Torchwood team (Ianto won't be returning, no matter how loud the fan protests get), there's the decision to be made as to how many episodes to make for Torchwood's fourth run. What's been revealed by Russell T Davies (although there's some debate as to whether he was announcing the decision or speculating on it) is that the show will be getting a full season, which suggests that we're not going to get an ‘event' season such as Children Of Earth next year.

What hasn't been expanded upon is just how many episodes that season will entail. Will the show be returning to the 13-episode format? Is it just us that would warm to the idea of perhaps having a shorter season, followed by another five-day story?

We look forward to some kind of formal confirmation in the months ahead, and wait with interest to see where Torchwood goes from here...