Major number is incremented when any user facing data or setting changes (ie, ~/.chrome might not be backwards compatible anymore 100% safely). Minor number is

Major number is incremented when any user facing data or setting changes (ie, ~/.chrome might not be backwards compatible anymore 100% safely). Minor number is incremented whenever. The number that is most important is the third number, the four digit build number, which increments monotonically and never resets. That is a more meaningful number than the first two, IMO anyways.