Here's the bit about how it functions:
"It works like this, when the avatar you are controlling hits an digital object, a signal is sent back via our SDK to Dexmo F2 and the small actuators actuates, brakes the joint and locks the exoskeleton. When you further bend your finger inwards, a normal force will be created on your fingertip."
According to the details on the site it seems to be part mo-cap rig for hands and part VR controller, which is what seems to be being pushed in the AMA. It also links up with the Stem controller system so that your strange metal hands can be placed accurately in virtual space:
It appears to be in the very early stages, as evidenced by the rough 3D printed prototype which Dextra says is fragile, hence the plan to make the final product out of metal. The early version has already been tried out in Unity to allow people to 'feel' surfaces, something that apparently took a non-Unity engineer a day to figure out.
However, you're not going to be feeling anything too subtle just yet. The servo-based system can currently only create a digital sensation. So no degrees of softness, just 'there' or 'not there'. Games about hard wooden blocks? Good to go. Games about stroking puppies are going to take a while longer.
It'll be hitting Kickstarter this month and if it gets funded they're talking about a $200-ish price tag depending on interest.