To clarify what wikidwombat states, I've done some research and it seems that GST (at 10%) is the only tax applicable to imports of digital cameras into Australia , unlike the UK where duty is also payable (I'm guessing as a value added tax, it is reclaimable if you're a business that's registered?) See: http://www.customs.gov.au/webdata/resources/files/HT85BW2012.pdf
-item 8525.80.10 (took a bit of digging -Aussie customs website is a bit dense!)
So, the calculation would be (I'll use US$ as it is still the world's 'go to' currency and prices in the US are generally quoted tax free):
US$6800 = AU$6590.42
$6590.42 x 1.1 (i.e. GST @ 10%) = $ 7249.46
Compared to the UK (cheapest list price £5299):
US$6800 = £4439.37
£4439.37 x 1.049 (import duty) = £4656.90
£4656.90 x 1.2 (Value Added Tax) = £5588.28
So assuming you intend to import the camera into the UK legitimately, it would not be worth buying it from the USA.
But in Australia’s case, it certainly would, so how do we get to $9990? My guess is that it’s either price gouging or the reasons is that dealers/Canon are covering themselves against currency market volatility. The Aussie Dollar is currently very high on the back of raw material exports to China:
Ten years ago AU$1.95: US$1
Now: AU$0.97: US$1
If the world descends into another recession then demand for manufactured goods will fall, leading to knock on effects that would lower the price of the Aussie Dollar. It would look very bad if Canon suddenly had to increase the list price in Australia, so they price the camera high and offer rebates or instant discounts once the cameras are available. In either case you'd expect the post-release price should be much lower, if this is not the case then buy it from abroad!