Depends exactly how it's done.
The kinect is made for xbox 360 and the drivers and dashboard for kinect are optmized to reach to the maximum speed with the less cpu power possible.
Kinect need about 10% from single xenon cpu (Xenon is a tri-core 6400mips x 3 = 132.000 mips and kinect needs a 10% of a single core from 6400 mips = aprox. 640mips for kinect.
You need to know that kinect use real-time detection for process all frames "onthefly" and of course, need cpu power. I don´t think that any "open source kinect" can be faster or more optimized than the internal drivers made by microsoft (by budget and years of development)
