It's got amazing symbolisms (both visually and through the dialogue), interesting allusions, is loaded with metaphors and parallels, and really works towards a single, very clear, central thesis. Not to mention that it's beautifully written and beautifully animated too. The conflicts and plot dynamic are also fantastic and serve as extended metaphors! Each of the characters represents something and there isn't a single detail that doesn't contribute something towards the overarching theme. I'm not even a fourth of the way through this series and already, it's a masterpiece.
I recommend Gosick to anyone who loves writing and the more intricate details and subtleties that make it such a beautiful art form. Cartoon buffs too! Gosick is one of those pieces of media that really challenges you to think really hard, but, if you do, the magnified experience is well worth the journey! It's an analytical paradise!
Just because I can't help myself right now, here is a link to the opening sequence. It's a good sample of the many things that make this show great!
http://m.youtube.com/watch?v=0Y6L21UxAew
#gosick #mustwatch