The uFactory web site has an update from this month that shows they've been optimizing the design. Their schedule to start shipping is May 1st. I don't see any need to worry about them not meeting their stated goals; it takes time to develop and collect all of the documentation and they're not going to do that if the design is still in flux.
I'll agree it's certainly not "open source" by the Richard Stallman definition; if it was then all of their docs would already be online. They're obviously trying to make a commercial go of it and assumedly don't want anyone beating them to the punch. In Shenzhen the nearest opportunistic cloner is probably next door 
As an aside, this just popped up on Thingiverse: Palletizing Robot Arm (3DOF, 50cm reach, 125g lift) by i-make-robots - Thingiverse