"Turn your PowerPoint presentation into an interactive online lesson. We call this a mix. Everything you need to create and share your mix is included. Add audio and video of yourself giving your presentation, write on slides as you talk to them, insert quizzes, practice exercises, and more – all from within PowerPoint. It’s like a screencast, but better. All you need is Office 2013 and the free Office Mix add-in."
"It's like a screencast, but better," the Mix testing site adds.
After downloading a PowerPoint add-in, Mix users can record audio or video of themselves giving a lecture; write and draw directly in PowerPoint as if it were a whiteboard; and obtain stats on who has viewed a particular Mix and how they've interacted with it (via quizzes, learning exercises, etc.).
To use Mix, users need to have PowerPoint 2013 or Office 365. (Testers who don't have either can get a free 180-day PowerPoint 2013 trial so they can test the app.)
With Office Mix, users can watch mixes on desktops, laptops and tablets running IE, Chrome, Firefox and Safari. Interactive lessons work on Windows tablets, Safari on iPad and Chrome on Android tablets. Lessons can be viewed as videos (but not used interactively) on Windows Phone, iPhone and Android phones, according to the Mix site.
Microsoft Research contributed to Office Mix. "Project Athena," a Microsoft Research effort, seems to be a backbone of the coming product.