The USB 3.0 Promoter group publishes the USB Power Delivery specification-- boosting the power USB cables and connectors can deliver to up to 100W, enough to power laptops and external HDDs.

The specification requires Power Delivery-certified cables for full 100W performance and enables a switchable power source without changing cable direction. It is compatible with existing USB cables and connectors and should coexist with the USB Battery Charging 1.2 specification and existing USB-bus powered applications.

The Promoter Group describes the specification as a step towards a future of "universal [USB] charging... most notably for charging notebook PCs using standardised USB power bricks."

The power boost also represents a move by USB against the new incumbent, Thunderbolt-- while USB 3.0 cannot match Thunderbolt in terms of data, Thunderbolt can only handle 10W of power.

Go USB 3.0 Promoter Group Announces Availability of USB Power Delivery Specification