YouTube has added new ways for channel owners to wrap other people’s content into their own playlists, should they wish to do so.
Their blog says “You can now feature any playlist from another channel as a section on your own channel by selecting the “Enter a playlist URL” option when creating a section from a playlist”
They add: “When you feature another channel’s playlist, its avatar will be shown along with the playlist title at the top of the section. With our new channel hovercards, viewers can more easily learn more about the channel.”
Finally, if you want to feature other channels, then you can do so via a “multi-channel” section on your page, as in this example:
You can read YouTube’s blog post about it here: http://youtubecreator.blogspot.co.uk/2013/09/share-love-with-new-cross-promotion.html