Wow. I'm not really sure where to start with this review, but... watch this movie. Seriously. All right, fine, I'll break down why:
Acting
So there are only really 5 characters in this movie - Omar, Nadja, Tarek, Amjad, and Agent Rami. The rest of the humans in the movie are basically extras. So there isn't much to say in the way of acting except: this movie is beautifully acted. Really, there was never a moment when any of the characters felt fake or forced, and even those rare instances that seemed like an actor had dropped character, it turned out to be incredibly subtle foreshadowing. All of the actors in this movie were wonderful, and all their acting was honest. What more can you ask?
Cinematography
I can't say I know much about film, but I can give you a layman's perspective - this movie looks really good. The shots are consistent, they're pretty pictures*, and they're not hard to follow at all. IMO, really good cinematography should contribute to plot / character development, not distract from it, and Omar's does this very effectively.
Plot
There isn't too much I can say without spoiling the film, but oh my god those plot twists. They kept coming one after another, and I never expected them. It was like if M Night Shyamalan actually knew how to properly direct. But don't worry, the ending was also incredibly satisfying.
Bottom line - watch Omar. And don't worry if you happen to be pro-Israel, or if you're not looking for someone to shove a political message down your throat. Omar is a really fantastic crime drama that happens to be set in the West Bank.
*That diction tho