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The new "Powerwall" link on the US Tesla website was there the evening of the Powerwall launch event. Are you referring to the Australia version of the site?
Has anyone checked out the official Tesla Motors website.
It now has a link for the Powerwall inbetween Superchargers and Updates
Deliveries begin Late 2015 (even for Australia?) http://www.teslamotors.com/en_AU/powerwall
So it looks like Powerwall may get here quicker than the D's or X's