It’s about time that Facebook (NASDAQ: FB) starting taking WhatsApp monetization more seriously. It’s long overdue, even by Facebook’s own standards. When Facebook acquired WhatsApp in 2014, the popular messaging service had 450 million monthly active users (MAUs). On the 2014 conference call to discuss the acquisition, CEO Mark Zuckerberg suggested that Facebook really only starts thinking about monetization once a service gets to 1 billion users: