According to MDS, China is retrofitting the facilities that they built for the upcoming Summer Olympics with western-style sit-down toilets after receiving complaints about their squat toilets. I'm kind of surprised that they didn't put sit-down toilets in all of the new construction that they're doing for the summer games. I didn't see very many squat toilets on my visit to China last fall and I assumed that they had pretty much stopped using them in new construction.
The strangest lavatory related thing that I saw in China was shared washbasins. In several places that I visited, instead of having washbasins instead of the men's and women's restrooms, a shared set of washbasins was placed outside of the restrooms. It didn't bother me, but I don't think it would go over very well in the west. From what I've been able to ascertain, there are a number of culturally significant rituals that are performed at the sinks in ladies rooms across the western world that most women would rather not have to conduct in full public view.