Exploring WhatsApp: Why Did Facebook Invest $19 Billion?

What's up with WhatsApp?<br/> <br />Why would Facebook, the most ubiquitous social network on the planet, pluck down $19 billion for a messaging service few have heard of in the U.S.<br/> <br />No.1 - Because WhatsApp is very popular internationally. Facebook says the number of messages sent on the app rivals the total number of text messages sent globally. It has 450 million active users, and the company says it signs up 1 million new users a day.<br/> <br />And in the world of social media - eyeballs are like gold, says Eric Setton, co-founder of rival messaging company Tango.<br/> <br />SOUNDBITE: ERIC SETTON, CO-FOUNDER, TANGO (ENGLISH) SAYING:<br/> <br />"Mobile messaging is so hot, because it is extremely disruptive. This is an app the people don't just install and forget about. It is something that they are checking 40 times a day, and I think that is extremely valuable. Combine to that the presence in emerging markets, where Facebook is not yet fully established and I think that makes it a very compel