Update: Since posting this story, Atari has made it clear it has no comment regarding the reasons for the ban. As such, I've contacted the OFLC for additional information.
One June 20, Rebellion's Shellshock 2 was refused classification in Australia. When we asked Eidos' distributor Atari if there were plans to edit the game and try for an MA 15+ rating, it replied in the negative.
We know the OFLC has a thing against excessive blood, decapitation and dismemberment, so I assumed it was one (or a combination) of these elements that earned Shellshock 2 an RC. Atari did provide a comment, but has since retracted the statement.