I'm not yet sold on mid-air gestures as a means of interfacing with a computer, and here's why:
A computer mouse is a precision tool, and back in the days of the original Mac's tiny 512×342 pixel screen, when the mouse made its popular debut, that precision tool was a great way to hit those tiny icons with accuracy.
Human gestures, on the other hand, are not precise. Unless you study kung fu or modern dance or are a neurosurgeon, chances are you simply don't have the muscle control to consistently perform very fine hand motions in mid-air.
It's my opinion that in order for gesture-based interface design to work, it needs to be paired with a flat physical surface. Not necessarily on-screen; I've found Apple's Magic Trackpad and the built-in trackpad of the MacBook Pro to be suitably precise. Placing four fingers on a flat surface and swiping sideways is easy to learn, easy to do and difficult to screw up.
That hasn't stopped Bellco Ventures from releasing their Ion Wireless Air Mouse Glove, seen up top. The wearable $80 device calls on the user to hold their hand in midair and point with accuracy at a screen, and watching the demo video, I'm not convinced:
Part of it is that the presentation is so poor that it's difficult to sit through. I found myself counting the amount of times the demonstrator said "Uh," as if sitting through a bad college lecture. But independent of that, do you think mid-air gesturing is going to catch on? When we first learn to drive a car, we don't have the fine muscle control in our foot to work the gas pedal with accuracy, so the car lurches all over the parking lot; but after time and practice we achieve a deftness. Do you think this device has merit, and that mid-air gesture control, with its attendant learning curve, will catch on?