Apple announced new Power Mac G5 models today, speed bumping the processors and lowering prices.
In addition to more power, all models except the low-end single 1.8 GHz configuration include dual-layer SuperDrives, which can burn up to 8.5 GB of data (or three hours of MPEG-2 video). According to Apple’s Power Mac G5 page, iDVD can handle the higher-capacity discs, something I’ve not seen as a capability for iDVD. I’ve asked my contact at Apple to clarify, but so far it seems that iDVD will handle it, which is very cool. However, I don’t know if commercial DVD players can read dual-layer discs.
[Update: According to my source at Apple, dual-layer DVD support was added in the iDVD 5.0.1 update released earlier this month.]