Version:           2.2.1 (using KDE 4.3.4)
Installed from:    Ubuntu Packages

it should be possible to append items (such as tracks from the collection, tracks from the playlist, or files/folders from Dolphin) at the end of the playlist by dragging them and dropping them at the end. however, this is currently impossible. the last possible drop position is instead just before the last track in the playlist.

this isn't a big deal when the items in question come from outside the playlist (although it should still be fixed for this case), since i can instead drop the items onto the "Add to Playlist" drop region. but this region is not available when dragging items that are already in the playlist, so in order to move tracks to the end of the playlist, i currently need to move them to the position before the last track, then move that track before the items. this is quite cumbersome.