Basically there is a hinge in the middle that rocks front to back. Under each corner is a rubber bit that press you energy into the edge. Depending on what feel you want you can change the hardness sort of like going for softer bushing or wheels on a skateboard. these vids explain it better than I can.
I have burton freestyles. How huge of an improvement are you noticing?
they're a major upgrade from the freestyles, and for almost $200 more they should be. i was sick as hell yesterday when i was trying them out so i couldn't really give them a thorough test and review but my first impression is they're pretty awesome. turn initiation is fast and easy and they definitely reduce chatter in bumpy conditions. the only issue i had was holding an edge at high speeds and washing out a little, but that very likely could have been my fault as i didn't have my normal leg strength.