If you go to this post: https://discussions.apple.com/message/19777603#19777603 there's a work around for you to be able to listen to your podcast.
Message was edited by: Mel823
Odds are that your playlist syncs, but Music on the iPhone won't let you see the playlists anymore. You can use Voice Commands to get Music to play the playlist by name. There may be other ways around it. Once you get one of the podcasts playing, Music behaves normally, even though it won't display the podcasts in the playlist.