mrcrispy83: eh, the anime is the weakest version of the series. The LN and manga each do their own thing, but then the anime tries to mix together elements of both (even though some elements/interpretations of the characters aren't wholly compatible) while watering down the content. Some of it might not matter, but not explaining about the sleeping pills probably hurts the plot a bit.
Well, obviously one of those agree-to-disagree things. I'd say that the anime made the characters much more relatable and likeable. In the light novel, the MC is a self-aware, self-ironizing whiner, but only in the anime does he become human. And his neighbour is given a much more prominent role, again to the benefit of psychological realism. To me, that's what the anime was about - an excellent study of depression and friendship, with the occasional hilarious moment. The light novel was, in contrast, lightly amusing comedy for the entire ride (except the end, where the two are the same), and the manga was almost a typical gag manga, not to mention it messed with the story to the point where I can barely think of it was belonging with the other two. I think the anime is highly regarded on every anime site I can think of for a very good reason, especially considering it's not about waifu or actiony boys or "hilarious" gags.
And the art/animation is pretty crappy because lol gonzo, to the point where they break the fourth wall to joke about it.
True, it's not very good. However, it personally never bothered me. I've seen plenty of well-animated, beautifully-drawn trash, after all.