Actor Norman Reedus Will Voice The Character
Drew Haworth, Creative Director at Terminal Reality has posted several details in relation to Daryl Dixon. "When we first decided that The Walking Dead videogame would be built around a single-player action-adventure prequel to AMC’s insanely popular series, there’s only one character that checked every “must have” slot... Welcome to the stand, Mr. Daryl Dixon. Really, who else would you want to play as in The Walking Dead?"
Drew went on to relate that Daryl's in-game dialogue has already been completed, suggesting that certain elements of the game's story are now inflexible.
Also mentioned was "that original dark blot of violence on mankind, Merle Dixon." Considering the nature of the game's story, Merle Dixon may factor heavily.
Source: PlayStation Blog