The fact that there is even a chance of this happening (with no mechanism to restore the playlists if it does) makes me very hesitant to spend all that time building up the playlists again and indeed I haven't done so.. which makes DJing much more difficult, with all the songs scattered and/or lumped together.
I guess I should give up on this feature and start organizing into folder structure, and have to duplicate song files that Cross over into multiple "playlists"
I would pay extra for a utility that could restore playlists via title or other metadata matching up to the files on the device/card