Man, I can't stand Australia. I sure as hell wouldn't want to have it there. But it does make sense, because a lot of the infrastructure is already there and Australia has the money to fund it. Relevancy in the football world is only important insofar as there are actual football fans. That's definitely the case in Australia.
Also, the World Cup was organised on African soil in 2010. It's far more likely to be organised in Oceania in the near future.