I'm really liking that rack concept. I'd probably want the bikes a bit lower... if the front fork support when behind (or in front of) the rear tire and curved around for the forks, one could conceivably have the bike lower than the roof level without sticking way out the back of the van. Hmmm, you've got me thinking.
Then again, I've been having dreams about one of these anyway... charge by solar panel, use as the most excellent around town or off road recon vehicle. Really light, electric, and sweet:
They even have a trailer hitch rack!