Engadget is reporting that an Australian news site has a direct quote of a "senior executive" at Telstra saying the following regarding the 3G iPhone:
http://www.engadget.com/2008/05/23/3g-iphone-to-support-42mbps-evolved-hspa-data/
"We know what is coming we have seen the new device and it will be available on our network as soon as it is launched in the USA. By Christmas this phone will be capable of 42Mbps which will make it faster than a lot of broadband offerings and the fastest iPhone on any network in the world."
http://www.engadget.com/2008/05/23/3g-iphone-to-support-42mbps-evolved-hspa-data/