No, Google's Doodle isn't celebrating Chrome's passing of Apple's Safari browser or knocking off any of Apple's products. The falling Apple is to commemorate the Birthday of Isaac Newton, who was born on January 4th, 1643.
Issac Newton's name was also the inspiration for Apple's previous tablet adventure, the Newton, which also died an unceremonious death at the hands of Apple.
Google's set to reveal their Nexus One phone at tomorrow's special event, though most of the details have already been leaked. It likely won't make a dent in the commotion caused by Apple's January 26th event however, which hasn't even been announced yet.