well they didn't ban Bioshock (hell, the designers were from/majored in Australia if Im not mistaken) and Metal Gear Solid 4. They both had really "illustrating" drug usage.
Hell, the end of MGS4 was 2 old men fighting over a needle if you look at it in a really...... bad way.
Read on: http://en.wikipedia.org/wiki/Video_g...ersy#Australia
even GTA4 was modified