Story: basically it is more of the same stuff, out cells doing their work and overcoming different situations. It is really nothing much to speak about, considering this season is only 2/3 of a normal season in length.
Art, sound: the same as S1, solid but nothing stellar.
Characters: once again, more of the same. Most of the characters were already established in the first season (or at least had episodical role), so you know what to expect. No real character progression if by chance you expected any.
Enjoyment: like I said, you will like it if you liked S1. I sure did and I kinda enjoyed S2, but without novelty of S1 it felt kinda stale and due to being only 8 episodes it also felt short.
Overall I don't regret the time I spent on it, but there sure are more interesting things to watch.
