Slipforms on steroids, ICF's (Insulated Concrete Forms)
OK, technically these are just forms not slipforms. But basically it's the same idea. You build the forms like legos, and then you fill them with concrete. ICF, insulated or insulating concrete forms. I haven't been able to find anywhere if you can fill the forms with papercrete or rocks and cement or rammed earth, which would be more the self-builder way. For sure you could not fill with cob, as it needs to breathe. I think the self-builder would want to go one row at a time, so even though the cost is comparable to a wood-frame house for a self-builder these would come out costing a lot, as you would have to buy them all at once. Unless you lived near a plant and hauled them yourself and maybe even picked up seconds.
Also all that concrete thermal mass is lost, because the insulation is on both sides of the concrete. They should make the inside panel of something that is permeable like wood not insulating material so that the concrete mass could help to store heat in the home modulating the temperature.
It seems to me the best system is Durisol, which is made from a cement-bonded wood fiber material with an insulating material inserted into the exterior side of the block. Here's a good article from Buildersnews. Lots of info here at the ICF Builders Network. Also the Green home builder has some info and links.