I read on another forum that a MacBook user, who did not have a mooing MB, applied this update, and then he noticed his fan on all the time. Now his silent MacBook is making noise, noise from the fan constantly spinning. Just a word of warning to those without the moo who like their MacBook as it is -- IF IT AIN'T BROKE, DON'T FIX IT! I do not think I am going to apply this update because I don't want my fan spinning all the time.