On Tuesday Apple released updates to both iDVD 4 and the GarageBand Jam Pack, as well as a firmware update for NVidia graphics cards.
The iDVD 4.0.1 update "is highly recommended for all users of iDVD 4 and will provide for improved reliability when authoring and burning DVDs."
GarageBand Jam Pack 1.0.1 "installs a number of additional effects presets."
The NVidia FCode flasher 1.1 provides compatibility with Apple's Cinema HD Display. It is only for versions of Mac OS X later than 10.2.3 with "an Apple Cinema HD Display and a Power Mac G4 with one of the following NVIDIA graphics cards: GeForce2 MX, GeForce2 MX TwinView, GeForce3, or GeForce4 MX. It is recommended that the user upgrade to the most recent version of Mac OS X (currently 10.2.8 or later) before updating to this flasher."
UPDATE Apple has apparently removed the NVidia FCode flasher 1.1 update. No reason was given. If you had previously downloaded the update, but have not yet installed it, we recommend not installing it until more information is available.