Take this with a football-sized grain of salt, but MacRumors and others are saying this COULD be the back of a next-generation 16GB iPhone, model number "A1303." The new case reportedly eschews the glossy appearance of the current 3G's for a matte-black look, and replaces the plastic back case with the hunk o' metal pictured. (The case also seems to be textured for better gripping.)
[Via MacRumors]
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