Channel owners can now feature one video on their channel page. You can feature an intro video, most viewed or latest video and you can change or removed the featured video anytime.
To select a featured video, simply go to your "My Uploads" and click on FEATURED VIDEO, the text will be highlighted once clicked. To remove, simply click the highlighted FEATURED VIDEO and select another video if you wish.
To feature a playlist on your channel main page, first you must have a playlist created (visit this link to know how to create a playlist)
Visit the "Playlists" tab on your account dashboard and click on "SETTINGS" on an existing playlist and tick the box that says "Features on channel homepage"
Note: You can only have up to 100 videos on a playlist and the entire playlist will not be visible to the public if one or more videos in it are on private status. Also, you can select as many playlists to feature on your channel.