[MetroMPG]

They also mention that some of the interior materials are pretty green too - in terms of natural and/or recycled materials.

Handling is probably fine in terms of slalom type manoeuvers - tadpole config is pretty stable. The red flag goes up though because oversteer is a lot more likely if the rear tire slides when cornering (from either braking or accelerating). They could minimize that danger somewhat with ABS & traction control.

Another potential issue with the center 3rd wheel is it will tend to be riding in the oily patch on the roads. And driving in snow might be a problem, since it doesn't track in the normal "ruts" made by traffic.

Then again, they're not planning to sell these things in the snow belt.