Yes, I have a dev kit and have played around with a it a bunch. I'm very impressed with the low latency and high framerate (~110 fps via usb 2, rumored to go higher for usb 3.0). Latency is unquantified but barely perceptible even when moving quite quickly.
The potential performance issue is with dropouts and interference. It's pretty easy to have detected fingers drop in and out, mostly due to fingers occluding each other. With a level of dynamics modeling/filtering built on top of the leap SDK, it may be possible to minimize the impact of dropouts.
overall, it does seem like a reasonable way to interact with a computer, especially for drawing or manipulating objects, etc.
I unfortunately can't post a video because we're building the leap into a trial clinical device at the moment and its out of my hands.