Take a look at this, UK gov is trying to make their country a global center for digital currency trade and fintech in general. They know how big of a potential bitcoin and the blockchain has when it comes to financial technology development.
Could facebook's User to User payment processor achieve any of this? Probably not.
Relevant:
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Nice, love the bitcoin community, these guys are fast at creating these nice and clear looking pictures that put things into comparative. Excellent for noobs that may think this is "bitcoin by mark zuckerberg" so to speak.