Russ Roca has posted a great review of the Bilenky cargo bike on his Bike Commuters site. After 300 miles of test riding, he says the Bilenky is better than the Xtracycle or LongJohn cargo bikes.
Efficient Cargo Bike: The Bilenky
The Gas-Free Transportation Guide: Commuter Bikes, Electric Bikes, Electric Scooters, Electric Cars