I've read some of the adventures you've had on your's and am highly jealous! With two kiddos and one one the way, it would be nice to get the kids out and about with one. I just can't justify the cost, let alone convince my wife we should get one. I currently transport the kids in a trailer and my eldest will be riding his own soon enough. It suits our needs.
If I lived in a city (and lived in one place for longer than 3 years) I would consider getting one.
I bet if Lane offered a class on how to build, he could still get funding coming in the door and leave the cost of frame ownership relatively low. With the population of LA and San Diego potential pools, it seems feasible....but I don't own and operate a bike manufacturing business.