The “Australia 2020 Summit — Initial Report” is available at: 
www.australia2020.gov.au/report/index.cfm
The Initial Report foresees, amongst others: 
A national and holistic tax system that is fair, simple and efficient to support the global competitiveness of Australia’s economy.
A comprehensive review of state and federal taxes within two years. This includes measures to simplify taxes and reduce inefficient taxes. 
Tax exemption [...]

Prime Minister Kevin Rudd has suggested a “root and branch” review of the tax system.  However, the GST rate will not change.  By world standards, Australia’s GST rate is modest.
There is nothing new, again by world standards, in politicians suggesting tax system reviews.  See David Martin’s work on Tax Simplification elsewhere on this website and my summary [...]