HUGE NOTE: THIS WORKS IN THE FULL VERSION OF THE GAME.
NOTE: THIS ALSO WORKS FOR THE GERMAN VERSION.
NOTE2: You can only play with people of your region code if you want to play uncensored. If you change your AppID to 510 and you try to play with someone who's AppID is 590, your game will be censored again.
NOTE3: If you're getting the "Could not load library client" error, apply all Steam client and L4D2 Demo updates, load L4D2 Demo through Steam, then apply the AppID changes again and run through the left4dead2.exe again.
Thanks to
Grimezy15's suggestions and my testing, we can remove the censor on the Australian version of Left 4 Dead 2's demo. This fix allows you to play Online and in Single Player without risk. That means ABSOLUTELY NO RISK OF GETTING VAC'D.
All you need to do is change TWO text files and you're set. You'll have to launch the game through the left4dead2.exe instead of through Steam. Steam will disconnect you immediately.
First file is found in \Steam\steamapps\common\left 4 dead 2 demo
Second file is found in \Steam\steamapps\common\left 4 dead 2 demo\left4dead2
That's it! Just run the game through the left4dead2.exe and you'll be able to play with all the gorey goodness the OFLC didn't want you to have.
EDIT: I had to re-upload the images to Cubeupload because of Photobucket's monthly bandwidth limit. Good work spreading the word enough to use 8GB bandwidth in just over a week.