Is there a site like opentape.fm or trntbl.me but for videos? Where people can create a playlist but with a minimal and clean interface. Must support youtube, other video sharing sites would be a plus but not essential at the moment.
You might like list4.me -- it's web app for creating online lists. Just add a link to youtube video as a list item and it will insert player for this video, so you'll get what you want.
It doesn't require any registration and very simple to use.
Here I've created an example for you, with few youtube videos: http://list4.me/s/e6608562