The USB 3.0 Promoter Group has finished the specification for its new, reversible USB connector design. First announced last December, the USB 3.1 Type-C connector is about the same size as the Micro USB connector, but it's symmetrical, which allows it to be plugged in upside down or right-side up with no ill effects. The design is similar to that of Apple's Lightning connector, and it should blissfully circumvent the USB quantum superposition problem.
Source: USB 3.0 Promoter Group.
According to the USB 3.0 Promoter Group, the Type-C connector is equally suitable for phones and notebooks, and it was conceived with higher speeds, greater power delivery, and future expandability in mind. It supports 10Gbps transfer rates (thanks to the USB 3.1 spec), can pump out as much as 100W of power to a device, and is primed for "future USB performance needs." (Presumably, then, 10Gbps isn't the upper limit.) The only downside is the lack of backward-compatibility with current connector designs, but the specification does call for "passive new-to-existing cables and adapters."
Now that the spec is complete, it's been transfered to the USB Implementers Forum, which will oversee "ongoing management and the establishment of a compliance and certification program." The announcement doesn't say when we can expect the first Type-C devices to turn up, but I assume it's only a matter of time.