Can an iphone 4 purchased at an Apple Premium Reseller in Hong Kong (i.e. factory unlocked) be activated in the US or does it need to be activated in HK?
As far as I know it doesn't matter where you activate it, e.g. I got my iPad 1st Gen. from the US and activated it in Germany.
Colleagues also buy iPads and iPhones from US and activate in Hong Kong.. ;-)