Personally, I found it to be more "interesting" than "entertaining," if that makes sense. I thought it had a great look, great sound design, an interesting/fresh/original concept, and excellent acting from everyone except those two little shithead kids. I thought it was great how they recreated the dialogue of the time and really imbued the film with a sense of time and place. Lastly, the fact that the story was drawn from actual records of the era was cool.
But despite all this, again, I'm not sure how ENTERTAINED I really was.