It is just a rumour, and it is not even a close date, but Australia might get Chromecast on May 7th. According to CNET Australia, 7 May is the target date for the Australian launch of Google’s Chromecast media streaming device.
Google did not provide any useful comment when contacted for the CNET article. They just said “We understand that everyone’s really excited about Chromecast but we don’t have a timeline to share about it coming to Australia.”
As I said, this is just rumour and dates might change. But I am sure Chromecast fans in Australia are excited already. Good luck guys!