It's all over town...David will be playing Dilios in Zach Snyder's adaptation of 300.
For those who haven't read the novel, Dilios is a fairly major character. He's a storyteller as well as a warrior, and he keeps the soldiers' morale high by spinning tales around the campfire. In the novel, when we first meet him, he's been entrusted with the all-important task of Main Character Exposition: recounting the story of young Leonidas' encouter with a wolf. (Side note: let us pause here and appreciate David's talent for exposition....from Faramir's lengthy Middle Earth geography lesson, to Carl's rambling explanation of the Van Helsing curse. That's not an easy thing to do, to hold an audience's attention while bending their ear with background information.) Chances are he'll be supplying a significant chunk of the narration.
More importantly, however, Dilios is the sole Spartan survivor of the Battle of Thermopylae, and it is he who carries the tale of their brave last stand to the cities and towns of Greece, uniting Greek citizens against the gathering forces of darkness and keeping the fragile flame of democracy alive. In a larger sense, he's the true hero of the story. He is the voice and the conscience of the soldiers, and one of Leonidas' most entrusted right-hand men.
Dilios also gets scratched in the eye during battle, so look for David to be sporting an eye patch about midway through.