There are a bunch of anime coming out for the fall season. See list here.
I think I will definitely check out Kampfer, To Aru Kagaku no Railgun, Seitokai no Ichizon, InuYasha -Kanketsu-hen- (The Final Act), and Kobato. These will give me a good mix of shounen and romance anime series.
The two series that I am the most interested in are Darker than BLACK: Ryuusei no Gemini and Fairy Tail. I was a fan of the first season of Darker than BLACK so I have high hopes for this sequel. As for Fairy Tail, I am an avid follower of its manga, so I am definitely excited to see it animated and voiced. I don't know how well they will produce Fairy Tail, but I think I will follow it no matter what quality.
Aside from those oncoming series, I am currently following Bakemonogatari, Bleach, Dragonball Kai, Fullmetal Alchemist, and Naruto Shippuuden.
Bleach is currently in the Zanpakutou filler arc, where the Shinigamis' Zanpakutou souls obtained "free will" from a villain called Muramasa and are

Naruto Shippuuden just spent two episodes covering Jiraiya's past and his adventure

Bakemonogatari (GhoStory) centers on Koyomi Araragi, a third year high school

Dragonball Kai is a remaster of Dragonball Z. I watched Dragonball Z from the Ginyu

Fullmetal Alchemist: Brotherhood is a remake of FMA that differs from the first

Alongside with all these series, I am watching finished series like Ghost in the Shell: Stand Alone Complex and starting To Aru Majutsu no Index and Fate/Stay Night.