An interesting article by Tourism Accommodation Australia here which makes a number of very valid points.
The plethora of short term rentals would obviously put upward pressure on rents for genuine long term renters and of course who wants their apartment block turned into a hotel.
Maybe the home owners who think they might embrace the Airbnb model might want to consider the taxation consequences of so doing. Firstly any income earned is clearly assessable. If you find your neighbour doing this a call to the ATO tax evasion hotline might be a starting point. It can be done anonymously.
Secondly if you rent out part of your home you may jeopardise the capital gains tax exemption of the family home. Something else to think about when looking to make a few easy bucks.