Kik, the messaging app, tokenized their entire ecosystem. I can see Facebook doing a similar play but perhaps for part of their products.

Whatsapp seems ripe for innovation, especially on the Payments side. Already many messaging apps such as WeChat provide payment functionalities, and their biggest competitor in India, Hike Messenger with 100 million users, have starting their own Payments system. A Whatsapp Payments system will easily drive Zuckerberg's net worth to over $100 billion