It looks like a 2-of-3 transaction with a mediator.. and these guys are trying to patent it.

"It is important to note that the idea is new, unique and un-obvious combination of processes of doing things that is protected as a defensive measure. Not anything invented by the core developers."

I'm pretty sure Mike Hearn described this a year ago..
https://www.youtube.com/watch?feature=player_embedded&v=mD4L7xDNCmA