The video shows the prototype and there are images of it standing on its own

The Poppy project is only 75% complete. When done it will be walking on its own. The high cost is do to the fact that it uses Robotis Dynamixel actuators:

21 Dynamixels MX-28 = $4,746 2 Dynamixels MX-64 = $612 2 Dynamixels AX-12 = $90

That's $5,448 just in servos. You will notice these research projects use Dynamixel smart servos that have serial communication, not supported by the ARC. Hobby servos are OK for hobbyists but not for serious researchers and universities. I wish DJ would add support for the Dynamixel actuators. I think it would be an excellent selling feature for buying the ez-b.

Since few people can afford over $5000 worth of servos in their projects, not sure how much demand there would be for the EZB to have that feature included... Each MX-28 servo cost $226... Yikes

They said their plan is for people to figure out ways to make them cheaper. Ie using cheaper servos etc. how that translates into the real world remains to be seen.
At least they are giving the plans away for free.

Serial is supported by ARC, you just need to use scripts to move them.