First 3rd Party Mac USB 3.0 Interface Benchmarked
Barefeats has benchmarked the first 3rd party USB 3.0 interface for the Mac from CalDigit:
"Wait a minute. Apple hardware and software does not support USB 3.0." Yes but CalDigit has developed OS X drivers for their PCIe and ExpressCard USB 3.0 host adapters.The early benchmark shows significantly faster sustained write speeds over both FireWire and USB 2.0 on the given drive, though no eSATA interface was available for testing. CalDigit claims it is the first and only card that allows USB 3.0 connectivity for the Mac. Apple has been slow to adopt USB 3.0 technology which promises faster access speeds for external devices. We haven't tried the interface, so can't vouch for it, and some forum goers have had some bad experiences with first generation product from CalDigit.
Apple was originally rumored to include USB 3.0 as early as this year into their Mac Pro line. The last Mac Pro update, however, offered no new upgrades in either USB or FireWire interfaces.