Microsoft has released the Windows 10 IoT Core for the Raspberry Pi 2. It retails for 75$ without the Raspberry Pi 2 Model B, or $115$ with it. Apart from the optional Pi, it is basically a pack of electronic components and an SD card that's pre-loaded with Windows 10 IoT. It is available at the Adafruit store, although both packs are currently out of stock… because of course they are.
Beyond jumper wires, a case, breadboards, resistors, LEDs, switches, and sensors, the pack also comes with a WiFi module. Interestingly, Adafruit claims that this will be the only WiFi adapter for the Raspberry Pi 2 that's supported by Windows 10 IoT. This is weird, of course, because Windows is kind-of the go-to when it comes to driver support. It makes me wonder whether Microsoft changed anything under the hood that affects hardware compatibility and, if it did, whether Windows 10 IoT loses its major advantage over Linux and other OSes in this form factor.
The kit is currently sold up, but retails for $75, or $115 with a Raspberry Pi 2 Model B.