Some good and _original_ series with excellent atmosphere from the last four years or so:
Haibane Renmei (obviously)
Kino no Tabi
Stellvia
Hundred Stories
Fumoffu (very well made slapstick-style comedy)
Noir
Princess Tutu

I'd include Last Exile too, and quite many would probably list the very recent Tsukihime. Last season also brought forward the incredible MoO. I'm too amazed by all the cool stuff to see any reason to complain.