Kamisama no Inai Nichiyoubi without a doubt! I've been itching to read more of the manga, so the anime definitely makes up for that.
I'm also looking forward to Dangan Ronpa,
Rozen Maiden, Genei wo Kakeru Taiyou, and Gatchaman Crowds. Tentatively looking forward to
Makai Ouji: Devils and Realist, and I'm planning on watching Free! but I have no expectations for it.
Oh, and I'm looking forward to
Gin no Saji too, but I'm not planning on watching past the first episode. I'm glad it got an anime, but I'm far more comfortable with manga, and with the manga already being as excellent as it is, there's really no need to supplement it with anything.
Also going to watch
Mirai Nikki Redial in the hopes of it fixing that horrid manga ending. One can dream, right?