I think I have a problem with Windows Media Player 10 and how I am trying to use it with my Samsung Yepp for listening to podcasts.
For me (control freak), I do not have any automatic synchronization setup. I basically walk down through the playlists created in Media Player by Doppler 2.0 Beta, and drag items I want to listen to my Sync List. Then I click on Sync, click Start Sync, and then all the files get moved over to the device.
So I disconnect from my computer, and listen to the shows on the Yepp, and then I come back and hook it back up. But Media Player doesn't seem to remember the "sync" relationship that I am imagining should be happening. Because if I delete something from the Yepp it doesn't get deleted from my library, and vice versa.
Which probably makes sense for "music" but for "podcasting" typically when I am done listening I really don't want the file anymore unless I might use the content in a future podcast that I am doing.
So ... my current work around is to just before I do the Start Sync process I take the Sync List and drag it to a temp play list, and manually do the delete after listening remotely. Otherwise you have an MP3 player full of obscure names that you have to go back through all the folders to find the right thing to delete.