Hmm...
Well first of all skateboarding is one of the most image-driven sports in the world so I don't see anybody using these weird wheels. Long-boarding may be different.
I'm not convinced about the lower contact area translating into noticeably lower rolling resistance. I would expect the hardness of the surface to have a greater affect on this scale. I could see these patterns deforming more than a traditional wheel and dissipating energy that way, resulting in "worse" rolling resistance. On the other hand, this pattern might deflect small rocks out of the path of the wheel, rather than bumping over them, improving rolling resistance.
As for sideways traction, the static and sliding friction should be the same because its independent of contact area. So then you're looking at a tread pattern looking for grip rather than a flat surface... it should have more grip.
I haven't though about wheels in a while, all I think about these days is processes.
