Microsoft today announced a $50 adapter that will allow you to connect your Xbox One Kinect to your PC, providing you with a potential use for the device even if you don't have it connected to your console.
The adapter is now available through the Microsoft Store. Combined with the $150 price of a standalone Xbox One Kinect, that brings the total price ($200) in line with that of the standalone PC Kinect (the Kinect for Windows v2 sensor) that sells for $200. You'll get an equivalent experience no matter how you get Kinect hooked up to your computer, though you will need a USB 3.0 port and Windows 8 in order to make it happen.
Microsoft also today announced that the latest version of the Kinect SDK, version 2.0, is now available to download for free. That's primarily of interest to developers, but better tools for developers means better software that they can build.
That's good news, because as of today, developers can sell Kinect apps on the Windows Store. As of this writing, there isn't much there--just three apps. That will presumably change given time; for now, you can try out a free app lets you scan items using Kinect to create 3D models which can then be 3D printed.