I finally got a chance to see MUD last week as well.
When I first saw the movie poster / marketing image, I had zero interest (even though I like Matthew McConaughey in his earlier efforts). But thanks to James B's great review, I wanted to give it a shot.
I'm glad I did.
This was one of the more surprising, genuine, earnest films I've seen this year. I don't remember much from the Tom Sawyer / Huckleberry Finn novels by Mark Twain. I remember I liked them when I read them back in Jr. High.
That being said, a modern remake sounded really intriguing, and I thought the young actors portraying Tom Sawyer and Huckleberry Finn did a great job, as did Matthew M. And I loved the "Southern Gothic" atmosphere that James B mentions.