Microsoft's Kinect for Windows program doesn't just involve new firmware for PCs. There will be a new version of the Kinect hardware designed for Windows, with "improvements" like a shorter USB cable ("to ensure reliability across a broad range of computers") and a smaller USB dongle to better share space.
The firmware includes support for a new "Near Mode," designed to see objects as close as 50 centimeters away from the camera ("with graceful degradation down to 40 centimeters," Windows Kinect GM Craig Eisler notes). It makes sense for a device you would use while sitting at the computer.
In advance of the Kinect for Windows launch (early 2012), Microsoft has launched the "Kinect Accelerator" program, which will give $20,000 each to ten startups using Kinect, along with Microsoft development tools, "marketing visibility" and mentoring.