Apple has extended its “Add more life to your Mac” promotion–which offers a US$50 mail-in rebate with the purchase Mac OS X 10.3 (Panther) and iLife ’04–until January 10, 2005. Interestingly, this is the first day of Macworld Expo San Francisco, hinting that the availability of either Mac OS X 10.4 (Tiger) or iLife ’05 could be announced at the show. The promo–which also offers $80 back with the purchase of the Panther Family Pack and iLife ’04 Family Pack–was originally scheduled to end yesterday. Apple said in June that Tiger, the fifth major release of Mac OS X, would ship in “the first half of 2005” for US$129.