Starting in iOS 7 you could already make audio-only Facetime calls person-to-person. But with the upcoming point release of Max OS X Mavericks, you’ll be able to place audio calls from your Mac as well.
Check out 9 to 5 Mac for the details.
You may recall that Facetime uses extremely high-quality audio for voice calls–much better than you can get over traditional phone lines. This will be big.
The video says it all.
From a press statement Apple released regarding US government requests for personal information:
conversations which take place over iMessage and FaceTime are protected by end-to-end encryption so no one but the sender and receiver can see or read them. Apple cannot decrypt that data.
So in short, Apple has reiterated (as of June 2013) that FaceTime calls and iMessages are secure and private, even from Apple. Even they cannot decrypt these communications.
The Verge and several other sources are reporting that you can now make free audio phone calls to your Facebook friends if you live in the US or Canada. You and the person you are calling will need to download Facebook Messenger for the iPhone. After that, it’s free audio calling. Plus free texting from app to app. You can’t beat free.