It's been a while since the USB 3.1 specification was finalized in August last year, but now we're starting to see some real-world implementations. At Computex 2014 I spotted three motherboards packing USB 3.1, giving system builders 10 Gbps of bandwidth and greater power ouput than what USB 3.0 provides.
The three motherboards on show were from Asus and MSI, both of whom are using custom implementations as the Z97 chipset - which these boards use - doesn't support USB 3.1. From what I understand, an extra chip on the board (an ASMedia ASM1142 controller in the case of MSI's board) uses a few PCIe lanes to provide USB 3.1's bandwidth.
The actual ports on the board appear identical to USB ports we've seen before, so there's no reversible connector just yet. In fact on Asus' motherboards, which didn't highlight the specific USB 3.1 ports, I couldn't discern which of the ports were 10 Gbps USB.
Both MSI and Asus say these boards aren't quite ready for a public release, and at the moment there isn't a lot of point in having USB 3.1 capabilities: just like SATA Express, thare aren't any products using USB 3.1 on the market.