I don't have a dual-layer drive, so I was surprised when iDVD '08 had been letting me select dual-layer as an option lately. (Of course I couldn't burn the disc, but I could save an image or VIDEO_TS folder.) But after upgrading this afternoon, this seems to have been 'fixed' (?). I created a new iDVD project and wanted to select dual-layer because of the length of the video, but the option was grayed out. I know it was the 10.5.1 update because I had a bootable backup of 10.5.0 and I booted into that version, opened the same iDVD project, and the option was alive again (not grayed out). So I selected dual-layer, rebooted back into 10.5.1, and the dual-layer setting is preserved, but the option to change is still grayed out. Does anyone have a good way to get this functionality back? Its almost like I need to fool iDVD into thinking I have a dual-layer burner somehow.