The concept is fascinating to me. Specifics are sparse on the site, it appears Mr Weisbrich has more ideas than money, but none-the-less, his ideas are interesting. The basis of his design would appear to use "passive amplification" to increase power density. In reality "passive amplification" is simply "efficient coupling". He is using aerodynamics to couple the wind more efficiently with his turbines. Like damming a river and concentrating the flow through turbines is more efficient than a waterwheel, using airfoils to accelerate a concentrated stream of air across turbine blades has the potential to improve efficiency. Increasing air speed is not "magic", it is science, and it looks like a brilliant application of science!
I would guess that the application of this particular design would require an economy of scale precluding hobby sized prototypes, but the concept might prove viable on a prototype scale. That is, building a scaled structure as pictured would be difficult, but building an airfoil to accelerate the air to a turbine is very possible. I can think of numerous schemes that would lend themselves to a small scale model. Very exciting food for thought!
The general idea is to use an air foil ahead of a turbine to channel more (read: faster) air to the turbine. From a Power point-of-view this would have the same effect as increasing the swept area of the turbine; however, because the turbine itself has a smaller diameter, and the air is traveling faster, the RPMs would be considerably higher than its larger counterpart. It might be possible to achieve 9m/s performance in 5m/s winds, and this would surely behoove the hobbyist! The power available in a 1m diameter turbine @ 5m/s ~57W; at 9m/s it is ~350W! To achieve this increase, the air foil must accelerate air from ~4.8m^2, but this is considerably easier to engineer (on a small scale) than 2.5m diameter spinning blades!
I am certain this idea is not new, but it is new to me, and I am quite excited about the prospect of thinking about it :-)