M.I.C. Gadget points to some apparent iPhone 4 prototypes on the chinese “grey market” with 64 GB storage capacities. The images could technically be easily faked but the “XX” on the back of the device’s do help represent the units as potential Apple prototypes.
If real and not hacked, this 64 GB iPhone 4 most likely represents a storage capacity that Apple decided to abandon for their 4th generation iPhone rather than an upcoming model. On the other hand, Apple released an out of the ordinary 16 GB original iPhone in February 2008 after the initial June 2007 4 GB and 8GB iPhone launches.