I found this on Team Liquid a couple of days ago and couldn't find a forum post about it so I figured I would post this here. It's a possible leak of concept art and placeholder animations for the final cutscene of Heart of the Swarm. People have commented on how the music is from Transformers and the voice acting isn't that great but others say it could all be placeholder. It seems like a lot of debate is going around about this but I couldn't find a clear answer as to whether it is fake or not.
 
  

This was leaked a few months ago... And I'm pretty sure it's real, Blizzard was working pretty quickly to take them down. 
 
EDIT: However, I wouldn't be surprised if they changed the ending a bit because of the leak.