It looks to me that 3 isn't the sole provider for the iPhone in Hong Kong. A banner on 3's website says "Available first at 3". Logic would suggest to me, they'd make more of an issue of it's exclusivity and use it as a selling point, if it were exclusive, and word it as "Only on 3", as is the case in the UK with O2. As it stands, it looks like 3 will be the first provider to launch the iPhone, with other carriers to follow?!
Three HK
Three HK