Editor's note : The following guest post is by Nikhyl Singhal , the co-founder and CEO of voice-application startup SayNow . Is it conceivable that one of our greatest inventions, the phone number, is about to face extinction? Just ask Mark Zuckerberg. Earlier this year, when asked if Facebook would be around in 100 years, as long as Ma Bell has been around, Zuckerberg responded, “I don’t know. But I don’t know how long telephones will be around for.” Will they be around for ten more years? I’ll go even further. It may not even take 5 years for the phone service, as we know it, to meet its demise. Who’s going to lead the charge? Voice on Gmail and Skype are just the beginning. What are Facebook, Apple, Yahoo, and Microsoft doing? As AT&T, Verizon, Apple and Google spent this summer hashing out plans for world domination , it seems that Facebook is best positioned to strike the fatal blow against our beloved carriers. And it starts with those phone digits.