The orcs will very much be the bad guys. This is the demon blood fueled Horde, not the noble savage Horde.
More than any of the technology, what I find interesting about "Warcraft" as a movie is the notion that this is a big fantasy epic with no clearly delineated "bad guys" in it. Instead, because players in the games can pick roles on either side, it was important to Jones to make sure to give both sides an equal voice in this conflict. "The Horde can be the heroes," he said, grinning. "I think this is the appeal. As you may know, 'Warcraft' is a project that was in development for some time, and they just were not able to thread the needle and figure out what would make it work as a film and still be referential to the game. And when I came in, my first pitch was, 'Look, when you play the game, you play as the Horde or you play as the Alliance, but you are the hero. This film has to do that, or it's wrong. I know it's not all about the game, but that is what makes it unique as a fantasy universe. And as much as I love 'Lord Of The Rings,' and as much as Peter Jackson broke the path for fantasy films, those are movies where the cute guys are the good guys, and the bad guys are the ugly ones and the monsters. This is an opportunity to take that trope and flip it on its head and say, 'No, good guys are all over the place, and the bad guys? You have to work that out.' That's a more interesting version of that original fantasy idea."
http://www.hitfix.com/motion-captur...-his-world-of-warcraft-unique-in-film-fantasy