Originally Posted by vurt 
"Placeholders"? It's a painting.
I hope they stick to the art style, it's nice to once in a while play something heavily stylized instead of the usual semi-realistic style almost every developer is going for.
Call it what you will. They're obviously temporary characters created for demonstration purposes. As such, they're holding the place of the real 3D characters, if the game is supposed to look like that.