Shacknews has a statement from CD Projekt indicating that the version of the Witcher 2: Assassins of Kings sold in Australia will be censored:

In order to obtain the rating in Australia, CD Projekt RED was unexpectedly obliged to make small changes to game content relating to the topic of sex as a reward. Since these changes are quite minor, especially relative to the total amount of content, they are unlikely to significantly affect the overall play experience.