One reason why Apple might be doing this is that it really wants to push iLife by making SuperDrives available to even more people, since a G4 iBook would allow it to have the SuperDrive, and thus the use of iDVD. Granted, this plan would make the high end iBook be similar to the 12" PowerBook, but a line can still be drawn between them by keeping everything other than the processor the same. The main differences would be no DDR, no line input, no dual monitor, smaller HD, slower tray-loading drive, and slightly bigger size and weight. I'll even bet that the 12" PowerBook will get L3 cache, DVI out, and 256MB built-in RAM on the next revision so that there will be some more differences... the same thing Apple did with the iMac G4 and the PowerMac G4. This move only means that 970-based PowerBook isn't that far off - perhaps the next revision?