It must be fascinating for Aussie culture to have the Asian Cup there. Their mainstream culture has been so tied up in the Anglo-sphere (see above) it must be really interesting for them to have all these countries who haven't been traditional rivals all of a sudden there.
Be a really interesting thing to study the coverage of the Asian Cup compared to say the cricket or other more 'traditionally' Aussie sport.
I think it is good that it is held in Oz, despite it's entrenched bigotry I wouldn't think that there wouldn't be much hostility in the stands or on the pitch between rivals such as Japan and China (or Iran - Iraq. or Sth Korea - Best Korea). Different setting and most of the supporters will be there to watch the football rather than seek redress for historical slights.
Having attended to a couple of major tournaments in Asia, I think one big advantage of having the cup in Oz was that they were able to tap into the various immigrant populations, leading to decent crowds throughout the tournament. Consequently, attendances didn't really suffer as much as they have in more countries with more homogeneous populations.
Probably helped that the Aussies went all the way, & sustained local interest too.