According to Shogakukan, Kuroi Ransuke’s novel “savannaGAME” was announced to get a TV anime adaptation. It will be aired in 2012.
Synopsis:
Shibuya Kazuya is a 24-year-old man and has been living a dull life as a part time worker. One day, he receives a strange e-mail, which invites him to a killing game approved by the government. The surviver will win ten billion yen. Kazuya decides to join the game with his friends Jin and Mafumi, but the game turns out to be far more insane than he expected.
Source: Shogakukan