It seems that Facebook has taken its time turning to the $Crypto space. The idea that they'll add a proprietary coin, rather than their own, isn't very likely IMO. The altcoin they'll develop will obviously be specfic to their platform. Facebook is absolutely in the big data market, which means to me, that DE-centralization isn't on their minds. Privacy isn't going to be on their agenda.
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From @leonard.caldwell