Saw the mitchelin web pages about their new tire a few days ago (Weeks?) and the design looks "interesting" My main concern is metal fatigue in the rim.
The purpose of air in the tires, instead of a hard steel rim with a rubber band around it, is to absorbe much of the small bumps and lumps in the road,, Example, a marble on the road (or a rock about the same size)
Now, major bumps (Speed bumps, pot holes, that kind of thing) are up to the shocks
With a solid steel rim the tiny bumps would be transmitted to the car, since this is bad, this new design makes the rim semi-flexable, This has a lot of advantages. However there is a downside too and that's the posibility of fatague in the rim, instead of the tire.