If you're looking solely at transfer rates, the USB 3.0 specification – with its 5Gbps speeds – may be plenty fast, but it already can't push the same amount of raw data as, say, Thunderbolt. New specifications coming down the pipeline, like SATA Express and external PCIe, are promising speeds that flat-out blow USB 3.0 out of the water. The USB Promoter Group's aiming to stay in the race with an innovative tactic; rather than compete solely with transfer rates, they're also turning the familiar USB connection into the equivalent of a 100W power cord.
Read more at: Maximum PC | New, Powered-Up USB Spec In Development