I just received my copy of Leopard that I ordered from Amazon.com, and tried to install it on my iBook G4. The machine meets all requirements, and everything seems to go fine. Then when it starts to install, it says something along the lines of "Can't upgrade because there are no files to be found" or something to that effect. I've tried it 3 times now, and it just won't work. However, it boots just fine into Panther (which is installed on the HDD). I've repaired permissions, ran fsck, and used the Original Software Install Disc to "repair disc" and it still won't work.