Yup and I believe that this giant companies will have to adopt in blockchain technology. If they didn't adopt blockchain technology, their competitors will be likely to succeed in the long run. And I've heard rumors that FB is recruiting more blockchain developers.
They have a plan to adopt it but not sure about to adopt it very soon. That rumor can't be trusted if there was no any clarification from the facebook itself. As far as i know that facebook only stated if they are interested to adopt blockchain but not sure if they have the mode plan regarding it.