It's been going on longer than you may think. I still remember the Howard government sucking Harradine's dick (by advocating net censorship) so he would agree to let them sell off Telstra.
I'm fairly confident that I can come up with a technical solution that will completely bypass this filter, but that does no good for the Average Joe, and still has long term ramifications for all Aussies... and other countries looking to follow suit.
This may be of interest, it's regarding a Finnish site that contained info on the country's CP filters. (No CP, just information about the censorship regime). Ultimately, the site itself ended up in the blacklist. (!!!)
http://en.wikipedia.org/wiki/Lapsiporno.info