I'll be genuinely honest when I say, I have been a hyped up fan of this series until I actually finished it, and frankly, I think that it has some points which require working but overall as an anime - and something which I find myself putting in the Shonen category because of its main character (referred from this point onwards by its Deadman Wonderland alias, Woodpecker).
Sound
I won't like, I love the theme song of Deadman Wonderland - its fluid, it captures the insanity and horrendous brutality of the landscape which the anime tries to establish (and does to a significant extent maintain) holds onto as it progresses in its 12 episode run. Actually, this anime has - in my opinion - a really good soundtrack overall. My personal favourite sounds though, were the theme song and the Corpse Carnival (or Carnival Corpse, as it would be announced in the subbed version) song (which incidentally reminded me of Cannibal Corpse - a nod to it perhaps).
As for story and art and characters, I'll only say that they were involving in the 12 episode run. They could be better, because it being Shonen it is understandable that Woodpecker is the weak link in this anime and only in the 11th and 12th episode does his potential start showing (to marvelous effect, in my opinion). Wretched Egg is an interesting character who they held back on for a future second season which (alas) will never happen. So far as the place itself is concerned, the art style captures the... brutal, gorish, sickening perspective that was the aim and intention of this anime. It has a few faults here and there though (episode 4 for instance, has a scene in which Woodpecker's face injury was omitted even though the remaining scenes maintain it again), but so far as the use of "horror closeups", and character development is concerned, it captured the mood. There are moments when it tends to have a witty angle, although I think that these moments were unnecessary as a result of which they distracted me from a good anime overall.
Credit where credit is due, I actually enjoyed this 12 episode anime for its unsettling atmosphere - but I'd watch it only as a fan whose psyched by the theme song and the Carnival Corpse events. Its mostly for fans who'd hold onto it if they like it - but not all would find it appreciable if they have seen say... Hyakumonogatari/Requiem from the Darkness, or Cat Soup or Shigurui. Certainly not a timeless classic, but a good anime nevertheless.