Transfer playlists to iPod without duplicating? (songs are already on iPod)

No Joe, it only copies the list, NOT the songs. All the songs are kept in the music library on the ipod. Playlists are just lists of songs from that main library. The songs don't exist more than once. However, if you have a playlist that contains a song that isn't on the ipod, then that song will be added to the main music library of the ipod too.

Get it?

Basically, it's what Patrick said, but I guess you didn't understand it.

Say you have a bowl of fruit with 3 apples 4 oranges and 1 banana and you and 2 friends each make a list of which fruit they'd like to eat from that bowl. You might say 2 apples and 1 orange. Friend 1 says 3 apples 1 orange and 1 banana. Friend 2 says 2 apples 2 oranges and 1 banana. Now in total, that makes 7 apples, 4 oranges and 2 bananas. But we know that the lists are just lists, they're not really fruit themselves. See?

If you select your iPod in iTunes and click the Music tab, you can choose which playlists you want to copy to the iPod. But the other posters are correct — copying a playlist will not cause the songs to be re-copied to the iPod, unless the songs have changed since the last time they were copied (new album art, say). And if that happens, the old ones'll just be overwritten on the iPod.

My iPod contains all of my playlists, but only one copy of each track. I.e., the music library on my computer is almost exactly the same size as the one on my iPod. If each playlist had a unique copy of each song, it wouldn't all fit on my iPod!

Also: if all of your music is already on your iPod, it shouldn't take more than a couple of minutes to sync the iPod, in which case all of your playlists will show up just fine. The only reason it would copy the songs again is if your iTunes tracks are different from your iPod tracks — new artwork, newly updated for gapless playback, edited fields, etc. If that's the case, letting it sync for a long time once will then enable you to sync quickly in the future.

Didn't mean to suggest you were a newbie; it just wasn't clear from your post that something was awry. If there are duplicate files on your iPod, there might be slight variations between the fields, or there might be something wrong somewhere.

Either way, just let your iPod auto-sync. That should delete all of the tracks currently there, and replace them with the library on your computer. If you still end up with duplicates, either you have dups in your iTunes library, or something is wrong somewhere and you should Restore your iPod.