Why?
1. The REACT unit is a dedicated unit established to fight tech-related crimes, and I would not take it lightly to know that they were investigating my conduct.
2. California's stolen property laws would appear to apply here and may well have been violated.
3. The much more serious federal Espionage Act of 1996 appears on its face potentially to apply as well - "Whoever, with intent to convert a trade secret, that is related to or included in a product that is produced for . . . interstate . . . commerce, to the economic benefit of anyone other than the owner thereof, and intending or knowing that the offense will, injure any owner of that trade secret, knowingly . . . steals, or without authorization appropriates, takes, carries away, or conceals, or by fraud, artifice, or deception obtains such information . . . shall . . . be fined under this title [i.e., up to $5 million] or imprisoned not more than 10 years, or both."
4. The "intent" element, normally hard to prove for criminal purposes, is strongly bolstered by facts admitted by Gizmodo (payment for the item, intent to get hands on Apple trade secrets, holding the property for an extended period) and is countered only by what appears to be the merest pretext of an excuse (supposed doubt about the genuineness of the item).
Maybe the first amendment will shield Gizmodo, or maybe the D.A., after investigation, will drop the matter, or maybe it is a stunt and Apple ultimately will not press charges, but if I were Gizmodo I would be concerned where this might lead.