Okay, I guess.
No, it's a very hi-quality leak. When it was posted on /mlp/ everyone just assumed it was just a troll with a fake video using preview caps as "proof" but then he began posting pics from the movie's credits with an "Everyone Dances" ending and the Storm King's mooks trying to put his petrified corpse together, as a "joke"
so it proved the leak was real and a lot of people began losing their shit.
Either way, looks like on the next hours this site will start receiving a lot of screencaps so be wary of spoilers.