Youtube has the "+" in the top-right to add videos to a playlist without opening and loading a new webpage, which is really nice!!

However, then we're also tasked with searching for the correct playlist to add the video to, which takes away from... everything <___<. In addition to adding a "+" drop-down menu for the video image links, try also including 3 or 5 hot-buttons that appear below the hypothetical "+" when a curser glides over the image. Allow a user to preset what playlists those hot-buttons are linked to, similar to the "+" button (not in a drop-down menu), because I usually only add to the same 2 or 3 lists anyway. Still include the "+" for the special case scenario.