So far the 2012 Winter anime season has been rather disappointing. It’s not that everything is terrible, but nothing strikes me as truly new and outstanding. The two best new shows are actually sequels.
Natsume Yujin-cho Shi (Natsume’s Book of Friends 4) is the fourth season of the long-running supernatural drama series. There’s really not much more that I can say about it at this point. It’s still excellent low-key storytelling. Since the stories are pretty self-contained you don’t need to have seen the earlier seasons (though it wouldn’t hurt.)
Crunchyroll is streaming all the Natsume Yujincho episodes in a single channel. The fourth season begins with Episode 40.