Apple has delayed its PowerBook G4 Combo Drive Upgrade Program, which was scheduled to start today, until January 28. The program offers owners of DVD-ROM- or CD-RW-equipped 550MHz or 667MHz PowerBook G4 systems the option to upgrade to a new Combo drive for US$299. Beginning January 28, orders will be taken at Apple retail stores and through a special phone order line. Upon verification of the PowerBook’s serial number and credit card information, the customer can have the upgrade performed at an Apple retail store or have a shipping box sent to them for installation at an Apple Repair Center.