It's also unfortunately one of the few ways to accept USD online in Australia, unless you hop through a ridiculous number of hoops with NAB (a bank)[1][2].

(BrainTree just launched in Australia[3], though. I'll be checking them out shortly for a project of my own. :) )

1. http://blog.angrymonkeys.com.au/why-being-an-aussie-startup-...

2. http://news.ycombinator.com/item?id=3098224

3. https://www.braintreepayments.com/tour/international