MacRumors report that the OS X 10.9.2 beta that has been released to developers includes FaceTime Audio.
With Messages, FaceTime, and FaceTime audio on iOS and OS X, Apple will have a complete communication system in place.
With a simple way to answer telephone calls and chat requests from all devices, those in Apple’s ecosystem will have little reason to resort to alternative VoIP apps when communicating with other Apple users. FaceTime audio is also a high-quality VoIP choice, as it uses the AAC-ELD codec for Full-HD Voice. AAC-ELD is designed to provide CD-like audio quality for voice calls, delivering high speech and audio quality at a low coding delay.
I love using iMessage. It allows me to reply messages while working on my Mac, without having to pick up my iPhone. Sure, I can do the same with Facebook messages and Google Hangouts but those require an additional step of firing up the browser. I still prefer to use a native app solution. The only service that comes close is LINE, with its Mac app.
It will be very useful to be able to make FaceTime Audio calls on the Mac. I have a feature request. Let me be able to shift between my iPhone, iPad or Mac during a call and it will be the perfect seamless experience.