Everything about this audiobook is superlative. Many audiobooks include incidental music, but few include ambient noise (rushing water, trains, crowds), and fewer still have used it in such an unobtrusive way, as a further aid to experiencing (and enjoying) the story. (Why don't more publishers do this?) Jim Dale's narration is wonderful. But one thing I haven't seen mentioned here -- in fact it is only confirmed in the last few minutes of the audiobook -- is that it uses the delightfully breezy and new translation by Michael Glencross (2004, Penguin). That in itself is reason to celebrate. I'm a big Verne fan, but never cared much for this one; but now I'd have to say it's easily one of my favorites. I expect to return to this recording many times.
What a pleasure it was to listen to this old story again. When I was a kid, I read it at least once a year, till I was in high school and "put away childish things." Dietz's easy-going story-telling style is perfectly suited to this book: you might just as easily be listening to tales of Lake Wobegon. He never quite loses the sense of innocence and child-like wonder that surrounds the story, but he captures the darker moments as well.
And dark moments there are. The plot, such as it is, hinges on a murder in the graveyard, guilt, courage, and fear. Later, the man who committed the murder is overheard planning to kill the Widow Douglas as well - committing other outrages in the process. Tom and Becky are lost in the cave, facing a very real possibility of starving to death in the darkness.
But Twain somehow manages to keep things in the realm of fairy tale; he was apparently storing up his harshest satire for the sequel.
There are many wonderful readers of Twain on Audible - I'm not sure you can really go wrong with any of them. But Dietz's rendition of this story is one of the best.