Put me down as someone who doesn't think John Fox is going anywhere. I think any possible hype over what Fox may do - ranging from the idea of him going to become the defensive coordinator of the Giants to walking so he can coach Buffalo - are terrible ideas. The most logical situation for him is to stay.
Still, this situation has legs, and people are dreaming it out. Some think Fox will leave because he wants to go, some just want him to go. Others fear he'll go.
If he does, the sway of Charlie Weis might help. Weis can't come to Carolina - I don't think Jerry Richardson would pay additional money for another bigtime assistant. For him to come, you'd have to fire close Weis associate Jeff Davidson, or find room for both otherwise without slighting either.
But, if Fox leaves, he has an out. Weis is immediately hired, as both would want. If Davidson's not retained, he gets them both. Add in Jim Skipper, and Fox has all the offensive guys he could realistically ask for.
So, if he actually does want to leave, this scenario is quite possibly how it'd play out.
Conversely, he has little sway over what he could get on defense, since most of it's new. Only third-tier assistant Mike Gilhamer is a loyal Fox guy. Fox may have hired the others, but they're all new and they all have an equal loyalty to Ron Meeks, who would have a shot at a promotion (which could at least keep him aboard long enough to ensure he's better off to stay). If one of the coordinators, or Skipper, were offered the head coaching job, they'd be likely to take it; Skipper makes the most sense, as it keeps assistants where they are other than him and keeps the staff relatively intact.
Either way, I'm securely in the camp hoping all stays the same, with hopeful exception to the retention of Danny Crossman or possible addition of Weis. I've heard rumors suggesting that Nick Goings may be a consideration to help on the special teams line in the future, and they could use his help.