Three new pieces of casting have been confirmed by HBO. First up, they have confirmed that Brian Fortune has been cast as “Night’s Watch Officer”, but that his role will basically fill that of the First Steward, Bowen Marsh, from the novel. Fortune has an official site here, and a showreel .wmv file here.
Besides this, the roles George had hinted at as being near to being announced—the wildling Stiv and Ser Kevan Lannister—are now filled. Stiv is played by Stephen Don, a Northern Irish actor. As to Ser Kevan, the younger brother and right-hand man to Lord Tywin, he’s played by Ian Gelder, who U.K. viewers may recognize from a number of genre TV show roles such as Torchwood and Robin Hood.
Here’s Gelder in a tribute video to his notable turn as Mr. Dekker in Torchwood: Children of the Earth:
ETA: Oh, and missed one, Hugo Culverhouse is cast as a stableboy. One with a brief, but rather final, scene.