I have concerns about negative gearing (we don't hold any investment properties) but I'm not sure Australia would be prepared for a rapid winding back of this tax concession.
Could you imagine the carnage among the Banking shares if thousands of properties hit the market because they couldn't cover their losses against other income.
Having three sons in their 20's we worry about their ability to buy a home without a crippling mortgage. No negative gearing would certainly slash home prices. Not sure of the impact on renters though.