This was the first "slice-of-life" anime that I've ever watched, too. The first that didn't involve violence and/or science-fiction. I guess that's what really drew me in to this anime, because the story was about life (and death) and people. And it was awesome from start to finish.
You can find everything in this anime. Fast pacing, unusual yet refreshing story, engaging and well-written dialogue, brilliant illustrations, outstading voice actors and actresses (I wonder, though, if they themselves have ever cried while recording, especially during the tearful bits), and the perfect selection of opening and ending theme songs. Need I say more? :P
Definitely the best anime of the summer. Next to Steins;Gate. They both get top honors, for me. :D