As promised, Microsoft has released a new preview SDK to go along with Windows 10 build 10158, released yesterday (and already superseded by 10159). The fast ring releases of preview SDKs are designed to allow developers to try out newest features and the latest bug fixes, and will include emulators for the latest releases of Windows 10 Mobile as they become available. Along with some API types receiving property and method signature changes, the new SDK includes two new related sets of APIs that allow IHVs (independent hardware vendors) and ISVs (independent software vendors) access to allow cameras to participate in Windows Hello authentication, the new feature coming with Windows 10 that will allow facial recognition as a method of logging in to Windows.
The SDK also adds capabilities to provide High Dynamic Range photo capture and photo generation for devices having VPS (variable photo sequence), along with a new Windows Photo Import API that will allow Windows Store and classic applications to import photos and videos from portable devices. According to the Blogging Windows post announcing the new SDK, "(o)ne of the key features of the PhotoImport API is that it runs in the background so that even if your app is suspended / killed, the import keeps happening."
You can check out the blog post for details on how to get the SDK, and how get your projects to make use of this newest preview.