There’s more info here, as well. Robin will be played by newcomer Jonas Armstrong. Keith Allen will play the Sheriff of Nottingham, Lucy Griffiths plays Maid Marian and Sam Troughton (grandson of Doctor Who‘s Second Doctor, Patrick Troughton, who played Robin in the 1953 BBC series) is playing Robin’s manservant Much.
They’re spending 8 million pounds on it, with financial assistance coming from BBC America — so I’m guessing it will probably air over here on that channel.
Post edited to correct dumb mistake.