The official WinHEC Hardware Conference page lists a session called 'Enabling New USB Connectivity Scenarios in Windows 10'.
The page reads, "Windows 10 introduces support for USB Dual Role and Type-C, which will enable new wired connectivity scenarios such a phone interacting with USB peripherals [also referring to OTG connectivity], or laptops connecting to an external display using the USB Type-C connector. This session will go into detail on how Windows supports these technologies and what you need to do to enable them."
Introduction of support for USB Type-C to Windows 10 will mean will help convince customers to move beyond the existing Type-A and Type-B connectors and ports used across millions of computers, peripherals and portable devices. Apart from supporting alternate modes, as Microsoft says, users will also benefit from the single connector type being reversible, making life easier by not having to check which way to insert a USB plug into a port. The same connector will also be used at both ends of a USB cable. In addition to supporting USB 3.1 speeds of up to 10Gbps (twice the speed of today's USB 3.0), the Type-C connector will allow for increased power delivery of up to 100W, which would be enough to charge a laptop or power an external 3.5-inch desktop hard drive as well as better resistance to electro-magnetic and radio frequency interference.
Detailing further support for alternate modes enabled by USB Type-C, the March 18 session listings topics, "Overview of the new use cases introduced with USB Dual Role and Type-C, What scenarios are and aren't supported for Dual Role devices, Using Alternate Modes (e.g. DisplayPort, Thunderbolt, or MHL) over Type-C, Support for Power Delivery, enabling devices to provide/consume up to 100W over USB, Hardware and software architecture changes for Dual Role and Type-C, and Building a Windows system with Dual Role and/or Type-C support." The Redmond giant also lists some intended audience which will include OEMs, peripheral manufacturers, and driver developers among others.