What the hell are you on Macca? In Australia the toilets are designed differently from ones in America (and a lot of other countries). The water in the bowls don't actually swirl around. In US (and other places, but I'll just call it that) toilets the water fills up the whole bowl and then drains. In Australian toilets the filling and the draining occurs at the same time (it creates a 'wave' kinda thing). Yes, water in the Southern Hemisphere does turn the opposite way to water in the Northern Hemisphere (see determination's post for the reason), but this does not affect Australian toilets.
And yes, in some (not all) toilets there is a choice for 1/2 flush or full flush.