The Revit user community creates many video tutorials. Below are links to some user-created video playlists.
Steve Stafford is a long time Revit user and consultant. Steve also regularly writes Revit tips and tricks at his blog Revit OpEd. Many of his articles include videos. The following playlist links to all of Steve Stafford's videos.
Aaron Maller is a Revit user who works for Beck Group. See the videos he has made avaliable to the Revit community.
The author of the Architect's Digital Design Guide, David, Beach has posted 26 of his Revit tutorials to YouTube.
LARUG (Los Angeles Revit Users Group) has created a YouTube channel of the presentations done at their events. A variety or Revit topics are discussed.
If you have your own playlist or know of other playlists, please add them to the list here. If it is your own playlist, consider adding the videos directly to the WikiHelp. Then embed the videos into the relevant help topic.