Big "me too" from hundreds of our attendee community watching many recorded lectures through our GoToStage channel. I keep getting requests for this from different people.
Great idea. I have a VHS tape player (you can guess at how old that is) that will play back at multiple fast speeds. Basically it speeds up the voice and cuts the dead space between words but keeps the original pitch of the person talking.
I would love playback at 1.5 and 2x speed. I want our internal team to see how the demo webinar went. The content is of course not targeted towards to my internal team and will be mostly trivial to them so increased speed would be quite appropriate.
Personally I find myself gravitating towards only using video players with increased playback speed.
Youtube has had this ability for ages. People can generally listen as a speed of 450 words per minute while people speak at around 150 WPM. There is plenty of use for this feature.
