It installs on all Macintosh systems with Bluetooth based on the Broadcom chipset.
Run System Profiler and click Bluetooth under Hardware to see the manufacturer of your Mac’s Bluetooth chipset.
Bluetooth Firmware Update 2.0 is available via Software Update and also as a standalone installer.
More info and download link (1.78MB) here.
[Thanks to MacDailyNews Reader “Macintosh” for the heads up.]