the BigDog was a good idea, but this?
not so much.
BigDog’s makers are working on a new quadruped that moves faster than any human and is agile enough to “chase and evade.”
Boston Dynamics, maker of the Army’s BigDog robotic mule, announced today that Darpa has awarded it a contract to build a much faster and more fearsome animal-like robot, Cheetah.
they also have a humanoid one they're working on.

Meet Atlas, Cheetah’s humanoid pal. Atlas is supposed to look more or less like the T-800 series of Terminators, minus the head. Its designers say it’ll be able to walk like a human over rough terrain, crawling on its hands and knees when necessary and turning itself sideways to slip through any narrow passages it encounters. Headless, with a torso and two arms, it’s a step up from Boston Dynamics’ other biped, the lower-body-bot Petman.