Redditor claims FaceBook audits conversations via mic. True? What are the facts?

Myth: Facebook is always listening using your microphone.

Fact: Nope, if you choose to turn this feature on, it will only use your microphone (for 15 seconds) when you're actually writing a status update to try and match music and TV.

http://www.snopes.com/computer/facebook/facebooklisten.asp