THere is a good article about all this by Wise at the Post:
A Williams Exit Would Be Well Planned
My bet is Williams will go, because he is going to be offered a "whatever you want" deal somewhere. He's got something to prove: that's he's not just a great coordinator, but a great head coach on the NFL. It's only if he's already decided to give it a serious SB run with Gibbs, come what may, that he'll stay.
I agree that the real question is about Blache and the assistants.