Some people might be upset since a Spanish actor is playing a non-Latin cowboy. However, since the studio is apparently looking at Jennifer Carpenter to play Susannah, they may not be using the character's races as they exist in the series as an unbreakable trait for the film adaptation.
film is being planned for a May 13th, 2013 release, but because the scripts aren't done, a budget can't be calculated and a greenlight hasn't yet been given. But apparently Universal remains supportive and we'll likely see this project get off the ground by late summer or early September.