Articles re some changes in the 2009 Budget:
Taxation of Expatriate "Expat" Foreign Income | My Tax Zone - TAX BLOG
Tax fears could spur an exodus of exodus | The Australian
It may differ in Australia, but I think there was a case in the UK involving a British pilot working for a European carrier, where I think it was ruled that each day when he landed in the UK, even though he remained airside, he was deemed to be in the UK for the purposes of caluculating his tax residence. (IIRC that case also turned on him having property and immediate family in the UK).