updated 08:35 am EDT, Wed August 1, 2012
Apple has finally started stocking the Thunderbolt to FireWire Adapter. The new dongle costs $29 and is currently listed as shipping within 1 to 3 business days. Although it can be used by any Mac with an available Thunderbolt port running OS X v10.7.4 or higher, its arrival has been most eagerly awaited by new owners of Apple's MacBook Pro with Retina display.
When Apple revealed the MacBook Pro with Retina display, it was so thin that a FireWire 800 port would not fit on the device. With USB 3.0 not appearing until the latest round of MacBook Pro refreshes, pro and semi-pro users were still relying on FireWire 800 external drives. This left current MacBook Pro Retina users unable to use their FireWire 800 drives until now, unless they also have a Thunderbolt display.
Apple says that the Thunderbolt to FireWire Adapter will supply up to 7W for bus-powered peripherals including FireWire hard drives and audio devices.