I got to see the movie here in wonderful Kuwait. I am also trying to get my hands on the poster. POSSIBLE SPOILERS AHEAD. I'll try my best to avoid them.
I thought the movie was pretty decent. The visuals were very good and I thought the fight scenes were engaging and the spells looked pretty rad. Without giving spoilers, I thought the major script change to the story was kind of like... what? It makes sense with how the orcs operate but I was kind of second guessing whether or not it was like that in the actual lore. Garona was portrayed really well. I'm convinced that there will be more to come with her and Medivh, possibly leading up to Med'an.
I think the movie was a solid 7/10. The issues I saw with it was the massive amount of back story behind the game (and all the lore in general) while the movie showcased a tiny slice of Warcraft history. There is a lot of backstory that is unexplained, specifically the important thing with Medivh. I thought the Mak'gora should have been explained a little bit better. That scene occurs, the orcs react, and my reaction was 'Oh, they just did the thing'. The main explanation in the movie is it's a highly regarded duel with the orc clans. Gah, there's much I want to point out about it but I would be giving away a lot of the ending. On top of the massive story, there are several jump-cuts from beginning to end. No joke, we're shown Ironforge with Lothar standing there, then it cuts to Stormwind and Lothar is there again. There's parts where the humans travel from Stormwind to Deadwind Pass or Blackrock Mountain in a simple cut. There is little sense of how much time it may have taken to get there, but that's a little gripe. The world definitely looks very large and grandiose throughout the movie.
On the acting side, I thought most of the characters were very well played. Medivh was by far my favorite out of the entire cast. Top notch quality, really well done.
There were also several easter eggs in the movie which were pretty cool. Frostmourne makes an appearance.
All in all, it's pretty good. The best way I've heard someone else describe Warcraft is it's kind of like the Iron Man movies. The first one isn't the greatest, but it lays down a good baseline to make future productions.