I picked up a new 2012 328i on November 17th, and it has VSS. I have the dreaded thunk especially over rough roads. Sounds like something is hitting something under the dash, but it's just noise from the steering gear (my thinking it is) coming through the steering shaft.
I also had someone move the steering wheel while I looked under the hood. The noise is definitely coming from the steering rack and steering shaft. If I'm stopped and shake the steering wheel left to right quickly, I get the same thunky clunky noise inside the car. I hope there is a fix soon and will follow these posts until there is. I don't really want to take my car in until I know where to tell the dealer to look.