As a kiwi, the brain drain is something that always bothered me. Right from the beginning of high school I knew that I would end up working overseas for several years, regardless of whether I really wanted to or not. And that's exactly what I'm doing right now -- I live in London, saving twice as much as I could in NZ. I don't enjoy the lifestyle here at all, and I want to go back to NZ as soon as possible to start a family, but the opportunities available in Europe (and the rest of the world) simply dwarf those available in NZ.
The good news is that immigration from Asia, India and the Pacific has given the country a significant population of people who culturally are more likely than Europeans to help with population growth. So who knows, maybe in 10-20 years the population will be large enough for the brain drain to sort itself out.