Description of problem:
The playlist argument is mentioned in the man page but the supported formats are not. It would be useful to mention the list explicitly or add a reference. Also there is a typo: ? show "keyboad" help.
Currently, the only supported playlist format is having one playlist item per line, which is basically a subset of M3U. The player does not support comments or meta-data information in the playlist.
gst123 rebased to 0.1.2 in rawhide, which fixes the manpage typo. I have opened a separate bug for the playlist support and its documentation. See bug 611636.