Which is correct?
Apart from a handful of larger companies (Google, Atlassian, Campaign Monitor) there isn't much of a software industry in Australia, and even then it's essentially limited to Sydney and Melbourne. Most developers work in-house for banks, the government, web agencies etc. I've met some very capable developers, but many of them are working in roles below their potential.
Longer term I fear that without a significant software industry, Australia will find it difficult to develop new talent and keep experienced top-flight developers from seeking greener pastures overseas. Personally I believe the high-cost issue will largely solve itself as the mining boom slows and the property bubble pops...
Median salaries are higher, but the standard deviation is lower. Part of this is because the effective minimum wage in Australia is $17/hr. (Benefits are likely more expensive in Aus than the US/Canada as well, particularly if you want to differentiate on giving above average holiday leave etc).
I believe that the article misrepresents facts to make a point that may or may not be there - the type of talent that you'd ideally want to attract (especially as an early-mid stage startup) is likely pretty close in cost to the same talent outside Australia. I'd think that there are more pressing issues (such as the tolerance/approach to failure, or differences in interest rates, which lead incubators to asking for much more equity for less money)...
Look at www.seek.com.au which is pretty much the premiere jobs site for Australia for prices
Senior Dev Roles in Sydney and Melbourne will get ~ $120k AUD per year with Brisbane and other state capitals generally dropping from there. Mid Level in Brisbane (3rd largest city) is generally $65k AUD. Orgs tend to be smaller here, so there are less managers / director / CTO roles then I have seen in the US. As such you can find it more difficult to climb the ladder.
On top of salary though there are a few extra expenses. Employer super is ~ 9% (going up to 12% in the future) on top of salary. States may (or may not) have payroll tax, and you likely also have to pay for things like WorkCover (which is an insurance scheme for injuries sustained at work). On the other hand most companies don't offer health insurance, etc as perks.
IMHO as someone who's worked in the US and now lives in Australia, that's a good thing! I'd argue that one of the major causes of the current health insurance fiasco in the US is the history behind health insurance being offered as a perk for good jobs. My health insurance (medicare & private) in Australia is completely separate from my employer and my employment status, and I very much like it that way.
In the US at my previous gig, I remember hearing older folks with health issues afraid to get made redundant because they would loose their health coverage. None of those fears exist in Australia.