I should be receiving my copy of leopard on Monday. I went to the Apple store last night for the launch and started playing around with the new OS. I asked the mac geniuses about my question, but they didn't know the answer. I am sure someone here on macrumors knows the answer. I have an external hard drive (mac os extended journaled) where I keep all my music. When I setup time machine on this external hard drive, will it need to erase the whole drive before creating its own folder? Has anyone personally had this situation where you already had docments, music, pictures, etc. on your external hard drive before configuring time machine? thanks.