Supersite for Windows posted Office Mix Preview
A quote from the article:
Microsoft this week launched a private preview program for Office Mix, which is currently available as an add-in for PowerPoint 2013 with SP1. Office Mix seems to be based in part on the PowerPoint Broadcast functionality that debuted in Office 2010, in that it publishes presentations to the public web. But it also lets you add audio, video and interactivity functionality, so that your presentations can become online lessons with elements like quizzes and exercises for the viewer.Office Mix Preview @ WinSupersite