Despite claims from Google itself, the newly-launched Chrome Web Store works perfectly well for Australian users, including with paid apps.
Google's own blog post on the subject seemed to suggest that, as usual, US customers would get access to this feature and everyone else would have to wait:
Right now the store is only available in the U.S., but will expand to many countries and currencies early next year.
Notwithstanding that statement, I managed to purchase an app on the store no problem using an Australian credit card via Google Checkout. After asking Google for clarification, I got told this:
Anyone with a credit card and Google Checkout can buy an app. It's launched on the .com domain, but there's no localisation.
Payments in Australian currency would obviously be better (you won't get foreign transaction charges for a start), but at least we have the option.