In a recent post Mark Zuckerberg showed his interest to learn more about cryptocurrencies in his 2018 Personal Challenge
and he also mentioned that he will study further on Implementing Cryptocurrencies on facebook this simply gives a hint that facebook could soon have posts being promoted over a blockchain based Cryptocurrencies.Which in turn we may be able to witness a strong competition between Steemit and Facebook.
Zuckerberg said " he will be looking into positive and Negative aspects of these cryptocurrencies and How They can be implemented in their Services"
You can read the complete post from Mark here!