The fever over Shaiya is reportedly due to some racy ads that prompted Chinese censors to request less suggestive promos. I'm sure the two half-naked women prominently featured in the game's propaganda had nothing to do with that. 17173 has collected some in-game screen shots and wallpapers of Shaiya's physical embodiments of "light" and "darkness" (can you guess who's who?).
See also: China online gaming trends