Deus Ex: Human Revolution was supposed to be out September 8 in Japan, but it's now slated for sometime in October. The reason for the delay is that "prohibited images" were found in one place in the game. In its official statement, Square Enix did not clarify what the offending content was.
In early August, Square Enix stated that the game would be sexual object free. In the Western version, there is a secret room. In it, you find a computer, a box of tissue, some lotion, and *cough* a dildo. Oh, and a vibrator. Since Square Enix said this would not appear in the Japanese version, it can't be the self-pleasuring goods.
It could be this section as the explicit depiction of the human body could rub the rating agency the wrong way. Any guesses?
Western games are often censored or edited when released in Japan for violence or adult content -- areas of expression that the Japanese rating board is strict. PC games, which are self-regulated, often feature adult content. Likewise, movies have more freedom to depict violence.
In Japan, Square Enix is releasing the game under its "Square Enix Extreme Edges" banner, which carters to harder titles. Deus Ex -- too extreme for Japan.
Kotaku is following up with Square Enix.
デウスエクス発売日延期のお知らせ [SQUARE ENIX EXTREME EDGES]