Microsoft has just announced that it's discontinued its 'Kinect for Windows v2' kits, meaning that going forward, anyone who would like to add Kinect functionality to their PC will need to purchase the 'Kinect for Xbox One' kit as well as a separate adapter.
Functionally, both the Kinect for Xbox One and Kinect for Windows v2 kits are identical; what was different was that out-of-the-box, the Xbox model wouldn't work with a PC, and the PC version wouldn't work with an Xbox. The option of purchasing the Xbox model and using an adapter has existed for a short time; now it's just forced. This mechanic is little different than purchasing an Xbox 360 or Xbox One gamepad and needing a separate adapter to make it work with your PC.
Those looking to add Kinect to their PC now will need to shell out $150 for the kit itself, and an additional $50 for the adapter. It's a big price to pay for what's currently a niche market, but we can hope that with Windows 10 right around the corner, Microsoft might have plans to help revitalize the Kinect for Windows marketplace. It'd be nice to see.