Just got this through Software Update. More info here:
I can't comment on the effectiveness as I removed my optical drive a while back in favor of a second hard drive.About MacBook Pro EFI Firmware Update 1.8
This update eliminates the noise made by the optical disk drive during system startup and wake from sleep on MacBook Pro computers. When installation is complete, please run Software Update again, and install SuperDrive Firmware Update 3.0
To complete the firmware update process, please follow the instructions in the updater application (/Applications/Utilities/MacBook Pro EFI Firmware Update.app). The updater will launch automatically when the installation is complete.