I have a Samsung YP-F1 ("Yepp"), and it's just a USB mass storage device, mounted the same way you'd plug in a thumbdrive.

You might need Advanced Partition Selection, though -- I followed the directions here:

http://www.shoalhaven.net.au/~glenalec/lit/non-fict/yepp-sports--howto.html

... and it worked just fine. Note that they're not for this particular model, but I thought it might be worth a shot and it was.

It's a lovely device :)